Without that refracting gaze, "The Mother" would feel tediously familiar indeed.
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Eventually, sunbeams started refracting from the brackish waters of the Hudson River.
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Social media is a prism that fame passes through, refracting in unpredictable ways.
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The design allows light to shine through, refracting off the shell's many facets.
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The scene is lit by sunbeams refracting diagonally through the room's vaulted windows.
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It houses what's billed as the world's largest refracting telescope and 170,23 photographic plates.
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CLEMENT And I answered by describing the atoms in the air refracting different colors.
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Does Larry Bell's big early abstraction fit the Vertigo section because of its refracting mirrored surfaces?
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The light painting is created by a group of lasers refracting through glass objects onto a screen.
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This creates a fantastic sight at night, with the corners of the glass refracting and scattering that light.
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It's in a curious position, refracting the insular country's representations of itself, trying to see what lies beneath.
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As usual, the drums are what destabilize the composition, refracting and undercutting the solemnity of the underlying orchestrations.
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So it's light from the sun reflecting off the moon's surface, and refracting off water droplets in the air.
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L'Engle's book derives its magic from refracting and magnifying Meg's pain, anger, and impotent rage into a fantasy quest.
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"Bonnie and Clyde" magnified the mystique of '30s bank robbers by refracting it through the lens of counterculture revolt.
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" Explains founder Carisa Janes, "The optically transparent particles alter the appearance of the skin by manipulating and refracting favorable light.
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Sunlight rakes through the windows, refracting through dozens of amber bottles and dappling the floor with a fawn-printed glow.
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And now the sun leans west like Cézanne, striking a rippling mirror of water refracting into a mirror of granite.
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"Bizarre Love Triangle" is a shining moment on their 1986 release Brotherhood, refracting synthpop light at every turn like a discothèque.
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Profile She's chronicled the messy stuff of life — refracting her own stories of heartache, addiction and loss — for over three decades.
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From another angle it's a perfect rectangle, with the cubes refracting and reflecting the landscape into an almost disco ball-like surface.
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Starting with The Thin Red Line (1998), Malick began fragmenting and refracting his films with the help of a corps of editors.
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Most days, the tropical sun bounces off the coral and sand, refracting into a hard light that gives many islanders a permanent squint.
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But we watch them, their radiance refracting tiny shards of light that act as mirrors, that reflect our own envy, our pride, our drive.
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Coincidentally, the cover of Dark Side of the Moon, released the same year as Laserium's debut, even depicts a laser refracting into a rainbow.
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Constantly bending, and abstracting, distorting and refracting, connecting and unifying concepts once the essence of an inspiring idea comes ashore like a special, invisible gift.
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CES doesn't create tech trends on its own, but it solidifies existing ones and focuses them by refracting them through a common lens: the consumer.
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The angle through which it is refracted depends on its angle of incidence to the refracting surface—an angle that, on a curved surface, varies continuously.
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In essence, the sheet's bumps and grooves act like the scales of a morpho's wings, refracting and diffracting the incident light to produce the desired effect.
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On the left is an approximately $4,000 telescope setup including an off-the-shelf refracting telescope, tracking mount, a camera, a cheap laptop, and stacking software.
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The artist's hand is visible in the image, holding a magnifying glass over the document, refracting her photograph and bringing out the paper's curved, pastel textures.
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Jessica Luther's UNSPORTSMANLIKE CONDUCT: College Football and the Politics of Rape (Edge of Sports, paper, $22000) similarly has football both refracting and magnifying a larger American problem.
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Refracting the past through the present, Winterson links automation, A.I., cryonics, and sexbots to the human yearning to transcend the aging, mortal bodies that we are born into.
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The show space was transformed by set designer Tony Hornecker into a nightscape with black vinyl flooring and disco balls refracting light, like shooting stars, around the room.
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The French astronomer Charles Messier (1730-1817) was fascinated by comets, and spent his life gazing through small refracting telescopes to identify new examples of these dynamic visitors.
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Nash is lionized in British art history for his attentiveness to the world around him — for capturing and refracting war and transmuting international artistic movements to his native England.
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Walls of jewelry reached up towards the ceilings, so intensely refracting the furious overhead lighting that it must have looked like if Times Square was built on the sun.
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In a new novel, " Revolutionaries " (Knopf), Joshua Furst has done Hoffman the historical-fiction honor of stealing his life and refracting it, slightly, into the tale of Lenny Snyder.
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The stories she tells M., embellishing and refracting her experiences, become a source of self-knowledge: "I began to remember something about myself I had been looking away from."
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He is not an anthropologist swooping in to study the primitive natives in their natural habitats, nor is he an Orientalist refracting "the East" through the lens of the West.
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" She too knows what it is to be Othered: "I was constantly refracting myself through multiple mirrors, wondering who I was perceived to be by others, how I perceived myself.
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Because Mr. Pluta was responsible for much of the vertiginous quality of these arrangements, refracting and spinning samples through a multispeaker mix, the live playing needed to be suitably crisp.
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But that everything-but-the-kitchen-sink songcraft has always felt like a distancing gesture, the sonic equivalent of a hall of mirrors, over-refracting simple sentiments instead of reflecting them.
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In teaser footage Lemercier recently published on Vimeo, we see one scene that feels like floating through an interstellar nebula, and another that turns the space into a massive refracting kaleidoscope.
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In l'Étoile, a ring of nozzles 16 feet high will produce a halo of mist that responds to the weather, refracting the sun on bright days and disappearing with the wind.
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Here he reprises a program heard last year at the Crypt Sessions, refracting Janacek's "On an Overgrown Path" through works by Mozart, Froberger, Rebel, C. P. E. Bach and Ofer Pelz.
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That refracting results in the visible disk of the sun being slightly stretched out (think of when the full moon is near the horizon and looks huge — it's being refracted too).
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That refracting results in the visible disc of the sun being slightly stretched out (think of when the full moon is near the horizon and looks huge — it's being refracted too).
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At the Royal Prussian Observatory in Königsberg (today's Kaliningrad in Russia), a daguerreotypist named Johann Julius Friedrich Berkowski carefully exposed a plate through a small refracting telescope attached to a heliometer.
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Additionally, she gave the artists an array of texts to which they fashioned responses, so the show ends up being a kaleidoscope, a variety of light wavelengths refracting through very disparate lenses.
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The A-side "Vuelve" is sprightly and fluttering, like a prism refracting a Francois Hardy song, and the flip is a bit more downcast, but each are full of life and light.
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It's the kind of view that makes you understand Thoreau: the sun cracks through the clouds, light bleeding into the haze and refracting a rose glow across the mountains, the beach, our faces.
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The bottles are then installed into roofs of houses and begin working as a mirror on the roof, refracting the light in 13 degrees and offering a natural light bulb during the day.
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A similar movement is achieved today with a smart electric upgrade: small LED lights below elegant prism glass pieces replace fire, refracting light in a way that mimics the subtle materiality of gas.
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She became indispensable to his work, helping draft his counterpoint treatise and enacting its musical principles in her new scores by "dissonating" melodies into disjunct figures and refracting rhythms in willfully independent lines.
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Rather, Americans' deep bias against the political party they oppose is so strong that it acts as a kind of partisan prism for facts, refracting a different reality to Republicans than to Democrats.
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Some of the kitchen staff lit off fireworks, holding the cardboard containers as the flares launched into the air, refracting off the towering wall of glittering ice until everything was bathed in flame.
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And most importantly, they come to realize that the Shimmer is a kind of refracting agent that's operating on the organisms inside in ways that are sometimes beautiful, sometimes terrifying, and certainly uncanny.
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In an interview with Hyperallergic last year about the monument, Goicolea described the prisms hidden within his boulders as refracting light in different ways depending on the season, day, weather conditions, and perspective.
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Refracting a nostalgia for the 80s and a love of capitalism through the prism of Trump, fashave projects an image of a looming dystopia, one that grows a little more plausible by the day.
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If crystals are organized patterns catching and refracting light differently, Andy Warhol's repeating Marilyn Monroes and soup can series are actually more crystal-like than his four-screen-print series Gems (303), hanging here.
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In its flowering, the phrase has been reimagined as a prism capable of refracting entirely new hues of meaning: schadenfreude, criticism, vague amusement and surprise, disappointment in society, self-deprecation, faux dismay, even bragging.
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If the early years had been about refracting an Animal House vision of college onto the internet, these golden middle years were about living an extension of the most slap-happy dorm room nights.
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"'Bonnie and Clyde' magnified the mystique of '30s bank robbers by refracting it through the lens of counterculture revolt," A. O. Scott wrote in his review of "The Highwaymen" for The New York Times.
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Ms. Driscoll's most ambitious project to date, the trilogy joins a body of work that is highly theatrical, refracting relationships and psychic states through movement, text, song and the use of unwieldy props and costumes.
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Astronomer Steven Bellavia, an engineer at Brookhaven National Laboratory, coincidentally sent me an image he took of the galaxy with a 71mm refracting telescope and 20 megapixel astronomy camera over the course of two hours.
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In commemorating the work of a female artist by largely refracting it through an imagined professional rivalry with another female artist, "The Dancer" seems genuinely hostile to its subject, whose real-life accomplishments deserve better.
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Beyond Vija Celmins's similarly rich yet spare exhibition of paintings at Matthew Marks, you might spend more time contemplating Ms. Barth's photographs of "blank" walls and refracting vessels than anything in Chelsea at the moment.
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And New York City — at least its more prosperous ZIP codes on the Upper East Side and in the West Village — also emerges from this novel as a powerful presence, reflecting and refracting the characters' moods.
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This involved refracting radio waves from the Earth's ionosphere—an upper layer of the atmosphere with a high concentration of electrically charged atoms—in order make contact with its units on the other side of the world.
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The Girls is also — like many recent stories about the Manson family, fictional and otherwise — a refracting lens for the stories of the Manson girls, which are also told in movies like the 2019 film Charlie Says.
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Kindly and self-skewering, Lamott, now 64, has been doggedly chronicling the messy stuff of life — refracting her own complicated stories of addiction and loss — in mordantly comic and sharply observed memoirs and novels for over three decades.
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Readers looking for a biography of the group will find some of the basics here, but it's how Abdurraqib filters the information — absorbing it, refracting it through his own distinctive lens — that gives this compact book its power.
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There is power in showing us the story that legal language constructs of Rodney Barnette's life and thus, her own, but there is more power in her possession of this language, in refracting it to amplify her own voice.
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Cacchione's curation veers away from the criteria of progress and linearity according to which Western art is typically evaluated, instead refracting Chang's works through the lens of his own bilateral practice, an infinitely yielding dialogue between painting and poetry.
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Mr. Deluc, working with the cinematographer Pierre Cottereau (and a lilting, moody score by Warren Ellis), emphasizes Tahiti's natural light and raw scenic beauty, as Gauguin would have seen it before refracting it into bold colors and rounded edges.
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In "Omeros" — the title is the modern Greek word for Homer — Mr. Walcott cast his net wide, embracing all of Caribbean history from time immemorial, with special attention to the slave trade, and refracting its story through Homeric legend.
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Instrumentally, Emily's D+Evolution rides a rich, organic jazz groove unlike any other; defined by Spalding's bass and Matthew Stevens's jangly, dissonant guitar, it's always shifting, crunching, changing angles, refracting shades of kaleidoscopic light through different colors, shapes, dimensions.
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By combining such sounds with the echoing cliffs of a Swiss yodel, or the lashing rain of Korean P'ansori, and refracting them through the mind of a composer, the group produces music that's both primal and sophisticated, ancient and startlingly modern.
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She's been doing her best to stay plugged into the bohemian East Nashville scene where she's long found kindred spirits among musicians who thrive on refracting the city's music history through the recalcitrance of indie rock and idealism of folk.
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On the floor, as high as your ankle and refracting the Baroque works on the walls, is an abstract construction of mirrored triangular prisms by the Antwerp artists Stéphane Schraenen and Carla Arocha — another work that produces drama through reflected light.
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Propelled by crystalline similes — sharp, clear, refracting — the work is disarming, tinged with sly humor or heartbreak, sprouting like a human head from a garden, as occurs in the 1977 piece "A Vegetable Emergency" from a book of the same title.
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Or consider the album's artwork (above), a black-and-white 60s style collage which, on the album's vinyl release, includes a color foil in its centerpiece of a woman's face—a shimmering spectrum of refracting light in the otherwise black-and-white composition.
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The National Trust doesn't allow modifications necessary to make somehting like Our Colour Perception, so West took an approach similar to her intervention in a North Lincolnshire cathedral, reflecting and refracting sunlight through colored mirrors, window panes, and prisms to transform the space.
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It was more than an hour until its 2100-inch Zeiss Refracting telescope would open for viewing the night sky, but already a line was forming of people wanting to get a closer look at the planets, the moon and the larger stars.
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Del Rey has always been a great imagist—crafting tangible visions of dirt roads and sparkling mansions—but here, she moves into the territory of timelessness, ripping compositions out of the great American songbook and refracting them through her unmistakable point of view.
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The drama of Wideman's personal history can seem almost mythical, refracting so many aspects of the larger black experience in America, an experience defined less by its consistencies, perhaps, than by its many contradictions — the stunning and ongoing plurality of victories and defeats.
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"Readers looking for a biography of the group will find some of the basics here, but it's how Abdurraqib filters the information — absorbing it, refracting it through his own distinctive lens — that gives this compact book its power," our critic Jennifer Szalai writes.
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Now that I've left the area, and the paper has made the jump into the digital age, it's become more like a funhouse mirror, refracting everything I loved and hated about growing up in the suburbs into absurdly shareable slices of life.
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Her debut album, Movement, channeled decades of computer music research from scholars like Max Mathews and Laurie Spiegel as it attempted to push the human voice to its furthest limits, refracting dynamic vocal audio through digital processes to give it an eerie, alien feel.
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In front of a window of a gallery in the Breuer building, Fred Eversley had planned to install a 72-inch pink acrylic disc, that when refracting light and images from inside the space and the outside world, would fill the galleries with pink, effervescent light.
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The collection sees Sakamoto assembling a veritable who's who of forward-thinking electronic musicians, with Oneohtrix Point Never, Arca and Yves Tumor and others reflecting upon and refracting 2017's glorious ambient excursion async – his first solo LP since being diagnosed with oropharyngeal cancer in 2014.
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Also the addition of sparkles and surprises: Dakota Johnson's burst of diamanté on her tulle bustle; Mary J. Blige's gauntlet/sleeve of rhinestones on one arm; the sprinkling of shine across the tops of Michelle Williams and her date, Tarana Burke, founder of the #MeToo movement, refracting the light.
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Part 2 captures the tumult of his movies from the 1983s, a period that found the director refracting his earthy style and Marxist worldview through the prisms of Italian neorealism, timeless texts ("Medea," on Saturday and Sunday, casts Maria Callas in a freehanded riff on Euripides) and cryptic symbolism.
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At times, the ensembles seem like allegories, as when the entire troupe lays their hands on one male dancer, fingers spread so their palms are to his skin; or the dancers are on their backs, the lighting now filtered indigo as they cycle their legs in the air, not exactly mirroring the runner — more refracting her.
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When even Antonio Marras, the champion of collage, of fantasy conjured from roses and lace and, this season, the coin-trimmed story of Adèle Hugo, combines pinstripes with his silvered appliqués, and Brunello Cucinelli, he of the Tuscan countryside idyll, tosses in some tailored herringbones refracting their own light, you know something is in the air.
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The album reminds me less of any other contemporary meditative electronica (chill vibe music is an industry now) than, say, the instrumental passages on a late Sonic Youth album (NYC Ghosts & Flowers, maybe) — a dazzled, skewed tour through a concrete pastoral cityscape, frequently stopping to admire the light refracting through windows and between skyscrapers, with occasional hushed voices that rustle like street conversations faintly overheard.
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Inspired by Mr. Koons's "Gazing Ball" series of paintings from 2015, which featured exacting reproductions of various masterworks (Manet's "Le Déjeuner sur l'Herbe," Monet's "Water Lilies," Klimt's "The Kiss") with blue reflective spheres normally used as lawn ornaments affixed on top and refracting the viewer, the collection comprises five of the most famous paintings in history, including the "Mona Lisa," Van Gogh's "Wheat Field With Cypresses" and Rubens's "The Tiger Hunt," all of which have been reproduced in high-definition detail on some of Vuitton's most classic leather bags.
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A convex plus a concave lens (f1 > 0 > f2) produces a positive magnification and the image is upright. For further information on simple optical telescopes, see Refracting telescope § Refracting telescope designs.
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A 200 mm refracting telescope at the Poznań Observatory A refracting telescope (also called a refractor) is a type of optical telescope that uses a lens as its objective to form an image (also referred to a dioptric telescope). The refracting telescope design was originally used in spy glasses and astronomical telescopes but is also used for long focus camera lenses. Although large refracting telescopes were very popular in the second half of the 19th century, for most research purposes, the refracting telescope has been superseded by the reflecting telescope, which allows larger apertures. A refractor's magnification is calculated by dividing the focal length of the objective lens by that of the eyepiece.
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The main observatory building offers free 15-minute guided tours of the Great Lick refracting telescope.
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Over the years, Custer has acquired a large collection of telescopes of all sizes and descriptions. Most recently, 10" Zerochromat refracting telescope and is the largest of its type in the United States. This is in the main observatory dome." Our 10” refracting telescope was manufactured in England by Zerochromat Telescopes.
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Because the image was formed by the bending of light, or refraction, these telescopes are called refracting telescopes or refractors.
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Light is decomposed by the prism, because its component parts are refrangible in different degrees, by the same refracting medium.
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George Bassett Clark George Bassett Clark (February 14, 1827 – December 20, 1891) was an American instrument maker and astronomer. Born in Lowell, Massachusetts and educated at Phillips Academy, Andover, he was the son of Alvan Clark, part of a family of refracting telescope makers in the 19th century. In 1846, George Bassett Clark joined his father and brother at the family's telescope works in Cambridge, Massachusetts. The firm, Alvan Clark & Sons, made many of the record-breaking refracting instruments, including the still-largest refracting telescope at the Yerkes Observatory, gaining "worldwide fame and distribution", wrote one author on astronomy in 1899.
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The second type is named the superposition eye. The superposition eye is divided into three types; the refracting, the reflecting and the parabolic superposition eye. The refracting superposition eye has a gap between the lens and the rhabdom, and no side wall. Each lens takes light at an angle to its axis and reflects it to the same angle on the other side.
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This refracting telescope is the largest ever built by an individual and the eighth-largest refractor ever built. Wall died on 27 January 2018.
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This eye type functions by refracting light, then using a parabolic mirror to focus the image; it combines features of superposition and apposition eyes.
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This association was dissolved after the inauguration in September 1965 and the observatory became property of the "Vereinigung der Sternfreunde". The university of Graz lend the CAA a refracting telescope with an aperture of 134mm and a focal length of 2000mm. This telescope was replaced by another refracting telescope from the company Wachter. Eight years later the CAA got the chance to make observations from the Gerlitze.
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Newton, Isaac. Optics, bk. i. pt. ii. prop. 3 From these experiments Newton concluded that no improvement could be made in the refracting telescope.Treatise on Optics, p.
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The Swedish 1-m Solar Telescope (or SST) is a refracting solar telescope at Roque de los Muchachos Observatory, La Palma in the Canary Islands. It is run by the Institute for Solar Physics of Stockholm University. The primary element is a single fused silica lens, making it the second largest optical refracting telescope in use in the world. The 110-cm lens has a clear aperture diameter of 98 cm.
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Refracting telescopes typically have a lens at the front, then a long tube, then an eyepiece or instrumentation at the rear, where the telescope view comes to focus. Originally, telescopes had an objective of one element, but a century later, two and even three element lenses were made. Refracting telescope is a technology that has often been applied to other optical devices such as binoculars and zoom lenses/telephoto lens/long-focus lens.
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He argued that a mirror shaped like the part of a conic section, would correct the spherical aberration that flawed the accuracy of refracting telescopes. His design, the "Gregorian telescope", however, remained un-built. In 1666, Isaac Newton argued that the faults of the refracting telescope were fundamental because the lens refracted light of different colors differently. He concluded that light could not be refracted through a lens without causing chromatic aberrations.
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The Fry 8-inch-aperture refracting telescope, manufactured by Thomas Cooke in the 1860s, at the University of London Observatory. In 1837 Cooke leased a shop at 50 Stonegate, York, with his wife running the shop and Cooke's workshop occupying the rear where he made and repaired whatever instruments were needed. He made a screw-cutting lathe for his own use. A notable instrument made at this time was a 4.5 inch equatorial refracting telescope.
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He used the law to produce the first Aspheric lenses that focused light without geometric aberrations.K. B. Wolf, "Geometry and dynamics in refracting systems", European Journal of Physics 16, p.
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As the incident wavefront approaches this critical obliquity, the refracted wavefront becomes concentrated against the refracting surface, augmenting the secondary waves that produce the reflection back into the first medium.
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The refracting prism is made of a glass with a high refractive index (e.g., 1.75) and the refractometer is designed to be used with samples having a refractive index smaller than that of the refracting prism. A light source is projected through the illuminating prism, the bottom surface of which is ground (i.e., roughened like a ground-glass joint), so each point on this surface can be thought of as generating light rays traveling in all directions.
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The "Große Refraktor" a double telescope with a 80cm (31.5") and 50 cm (19.5") lenses, was used to discover calcium as an interstellar medium in 1904. Astronaut trains with camera with large lens Refracting telescopes were noted for their use in astronomy as well as for terrestrial viewing. Many early discoveries of the Solar System were made with singlet refractors. The use of refracting telescopic optics are ubiquitous in photography, and are also used in Earth orbit.
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467,470; Boutry, 1948, pp. 601–2. In the same year he designed the first fixed lens – for spreading light evenly around the horizon while minimizing waste above or below. Ideally the curved refracting surfaces would be segments of toroids about a common vertical axis, so that the dioptric panel would look like a cylindrical drum. If this was supplemented by reflecting (catoptric) rings above and below the refracting (dioptric) parts, the entire apparatus would look like a beehive.
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For an achromatic doublet, visible wavelengths have approximately the same focal length. Hooke, 18th century. The achromatic telescope is a refracting telescope that uses an achromatic lens to correct for chromatic aberration.
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In optical instruments, dispersion leads to chromatic aberration; a color-dependent blurring that sometimes is the resolution-limiting effect. This was especially true in refracting telescopes, before the invention of achromatic objective lenses.
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Construction was completed in 1854, and the building was named the Detroit Observatory to recognize the benefactors who funded its construction. The building housed a 12⅝-inch (32 cm) Henry Fitz, Jr. refracting telescope in the dome. The Fitz was the third largest refracting telescope in the world when it was installed in 1857. A 6-inch (15 cm) Pistor & Martins meridian circle was installed in the east wing, while the west wing served as a library and office space for the director.
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Construction of the observatory started in 1808. While it was completed in 1810, setting up the necessary instruments took a few years more. The last of them was the Fraunhofer Great Dorpat Refractor, that was the largest refracting telescope at the time and was constructed in 1824.The History of the Old Observatory It has been titled as "the first modern, achromatic, refracting telescope".Fraunhofer and the Great Dorpat Refractor, Waaland, J. Robert, American Journal of Physics, Volume 35, Issue 4, pp.
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It was grounded ca. 1980 by György Kiss, who was an amateur astronomer. When he died in 2000 István Zahorecz became the new director. Nowadays it has six telescopes: five reflecting and a refracting.
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Titan was the first known moon of Saturn, discovered in 1655 by Christiaan Huygens. In 1655, using a 50 power refracting telescope that he designed himself, Huygens discovered the first of Saturn's moons, Titan.
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Views of a Leeson goniometer. The double refracting crystal was at a. From John Quekett's Practical Treatise on the Use of the Microscope (1852). The text comments that a Rochon prism could also be used.
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The refractive quality of lenses is frequently used to manipulate light in order to change the apparent size of images. Magnifying glasses, spectacles, contact lenses, microscopes and refracting telescopes are all examples of this manipulation.
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It was the largest refracting telescope (a telescope with a lens) in the world from 1852 to 1857, erected near London, England. It was a great refractor, a large refracting telescope with an achromatic doublet with an aperture of 61 cm (2 feet or 24 inches) and was completed in 1852 on Wandsworth Common and dismantled around 1857 (although the brick tower probably survived until 1870).The Online Museum of the Craig Telescope (www.craig-telescope.co.uk) It had a focal length of 76–83 feet.
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In 1872 he bought an refracting telescope with which he observed the transit of Venus in 1874 and in 1886 imported a Grubb refracting telescope and housed it in a substantial brick observatory building on his property at Windsor. The telescope later went to New Zealand but was returned to Australia at the time of the Australian Bicentenary and rehoused in its original location. Hawkesbury City Council now owns the telescope. Tebbutt spent his whole life at Windsor, devoting most of his time to astronomy.
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Dutch eyeglass maker Hans Lippershey tries to patent a refracting telescope (the first historical record of one). The invention spreads rapidly across Europe, as scientists make their own instruments. Their discoveries begin a revolution in astronomy.
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Telescopic beam expanders include refracting and reflective telescopes. A refracting telescope commonly used is the Galilean telescope which can function as a simple beam expander for collimated light. The main advantage of the Galilean design is that it never focuses a collimated beam to a point, so effects associated with high power density such as dielectric breakdown are more avoidable than with focusing designs such as the Keplerian telescope. When used as intracavity beam expanders, in laser resonators, these telescopes provide two-dimensional beam expansion in the 20–50 range.
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3 that all refracting substances would diverge the prismatic colors in a constant proportion to their mean refraction. From these experiments Newton concluded that no improvement could be made in the refracting telescope.Treatise on Optics, p. 112 Newton's experiments with mirrors showed that they did not suffer from the chromatic errors of lenses, for all colors of light the angle of incidence reflected in a mirror was equal to the angle of reflection, so as a proof to his theories Newton set out to build a reflecting telescope.
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The James Lick Telescope, shown here in an 1889 drawing The James Lick Telescope is a refracting telescope built in 1888. It has a lens in diameter- a major achievement in its day. The instrument remains in operation and public viewing is allowed on a limited basis. Also called the "Great Lick Refractor" or simply "Lick Refractor", it was the largest refracting telescope in the world until 1897 and now ranks third, after the 40-inch refractor at the Yerkes Observatory and the Swedish 1-m Solar Telescope.
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Among the notable instruments the company built were the telescopes for Lick Observatory (1888, 36-inch, refracting); the United States Naval Observatory (1893); Yerkes Observatory (according to the 50th- anniversary book,. this was a 40-inch refracting telescope completed in time for display at the World's Columbian Exposition of 1893, although its installation at Yerkes was apparently in 1897); and Canada's Dominion Astrophysical Observatory (1916, 72-inch, reflecting). In 1919, the company's founders donated their private observatory in East Cleveland, Ohio to Case Western Reserve University. Today's Warner and Swasey Observatory grew from that facility.
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By means of a water-filled telescope, Airy in 1871 looked for a change in stellar aberration through the refracting water due to an ether drag. Like in all other aether drift experiments, he obtained a negative result.
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This chromatic difference varies from about 400 nm to 700 nm across the visible spectrum. In LCA, the refracting properties of the eye cause light rays of shorter wavelengths, such as blue, to converge before longer wavelength colors.
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Kennedy's first love however was astronomy. Royalties from his book had helped fund an observatory he built at Meeanee. In July 1907 with a nine-inch photo-visual refracting telescope he opened a new observatory in Meeanee observatory.
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Canadian playwright George F. Walker's 1988 play Nothing Sacred is a stage adaptation of Fathers and Sons."Refracting Russia Through the Present". Newsday, 23 October 1992. Irish playwright Brian Friel has also adapted the novel, under the same title.
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The band had composed and refined the material while touring the UK, Japan, North America and Europe. Producer Chris Thomas assisted Parsons.: (secondary source); : (primary source). Hipgnosis designed the packaging, which included George Hardie's iconic refracting prism design on the cover.
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McCormick donated funds for a refracting telescope to the University of Virginia. The telescope and building are known as McCormick Observatory and opened in 1885; the telescope was the largest in the U.S. and second largest in the world when completed.
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The space observatory, equipped with a seven-inch refracting telescope and two smaller telescopes, forms one of the departmental teaching laboratories. This is the oldest observatory in the country, and has remained a centre of learning for more than 75 year.
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In 1856 Huggins acquired a 5-inch diameter aperture telescope by Dollond. In 1858 an 8-inch telescope by Clark was added. These were both refracting telescopes. (glass objectives) Huggins also established an 18-inch diameter reflecting telescope in 1870.
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It was named after the Rev. John Craig, who spent a small fortune on it, producing a uniquely designed telescope with nearly double the aperture of the next largest refracting telescopes, making it the largest refracting telescope in the World for the better part of a decade. However, it had a problem with its lens figuring starting from its first light in the summer of 1852. It soon fell into disuse as that same year Craig lost his only son, then his wife in 1854, and lost his brother and was put in jail for 6 weeks in 1856.
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Mount Hamilton (California) The first telescope installed at the observatory was a refractor made by Alvan Clark. Astronomer E. E. Barnard used the telescope to make "exquisite photographs of comets and nebulae", according to D. J. Warner of Warner & Swasey Company. The Great Lick refractor, in an 1889 engraving The refracting telescope on Mt. Hamilton was Earth's largest refracting telescope during the period from when it saw first light on January 3, 1888, until the construction of Yerkes Observatory in 1897. Warner & Swasey designed and built the telescope mounting, with the lens manufactured by one of the Clark sons, Alvan Graham.
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The difficulties with the impractical metal mirrors of reflecting telescopes led to the construction of large refracting telescopes. By 1866 refracting telescopes had reached in aperture with many larger "Great refractors" being built in the mid to late 19th century. In 1897, the refractor reached its maximum practical limit in a research telescope with the construction of the Yerkes Observatorys' refractor (although a larger refractor Great Paris Exhibition Telescope of 1900 with an objective of diameter was temporarily exhibited at the Paris 1900 Exposition). No larger refractors could be built because of gravity's effect on the lens.
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His Newtonian with a mirror diameter of compared favourably with the large aerial refracting telescopes of the day.The complete Amateur Astronomer – John Hadley's Reflector The size of reflecting telescopes subsequently grew rapidly, with designs doubling in primary mirror diameter about every 50 years.
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With the inheritance of his passed uncle he decided to acquire a refracting telescope Steinheil of 120 mm. aperture and 1800 mm. focal length. Due to the size of all his new equipment he needed to acquire a dome to protect it.
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Olympus M.Zuiko Digital ED 300 mm f/4 IS Pro is an optically corrected telephoto lens. With its extreme focal length of 300 millimetres it is the refracting prime lens with the longest focal length of the Micro Four Thirds system (end of 2016).
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1922 saw the addition of an astronomical observatory with a 4-inch Bausch & Lomb refracting telescope. These items were gifts from the Wellington Alumni Association in memory of Prof. R.H. Kinnison, a former Superintendent of Wellington Schools. His hobbies included astronomy and related sciences.
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In 1880 he co-founded a business to manufacture machines with Ambrose Swasey. The firm, Warner & Swasey, was initially located in Chicago but soon moved to Cleveland., p. 19. Worcester Warner would design the 36-inch refracting telescope installed at Lick Observatory in 1888.
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The field lens - by behaving as a variably angled lens - solves this problem by bending or refracting the cone of light back into the succeeding relay lens. In X-Ray microscopy, the field lens is used to produce parallel and homogeneous illumination of the stencil.
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Now, refracting at T1 a ray r3 coming from S2 we can calculate a new point B3 and corresponding normal on the bottom surface using the same optical path length S22 between S2 and R2. Refracting at B3 a ray r4 coming from R1 we can calculate a new point T3 and corresponding normal on the top surface using the same optical path length S11 between R1 and S1. The process continues by calculating another point B5 on the bottom surface using another edge ray r5, and so on. The sequence of points T0 B1 T1 B3 T3 B5 is called an SMS chain.
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The 100 inch (2.54 m) Hooker reflecting telescope at Mount Wilson Observatory near Los Angeles, USA A telescope is an optical instrument using lenses, curved mirrors, or a combination of both to observe distant objects, or various devices used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. The first known practical telescopes were refracting telescopes invented in the Netherlands at the beginning of the 17th century, by using glass lenses. They were used for both terrestrial applications and astronomy. The reflecting telescope, which uses mirrors to collect and focus light, was invented within a few decades of the first refracting telescope.
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The principal telescope at the observatory is a refracting telescope. the objective lens was made by Alvan Clark and Sons. The telescope, which was finished in 1882, was installed at the Halsted Observatory of Princeton University. The telescope was rebuilt in 1933 by J. W. Fecker Company.
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The company was founded in 1988 as Synta Optics, at first producing only eyepieces. In 1992, the manufacturing was moved to Suzhou (Jiangsu) in China. Their first telescopes (4.5“ (114 mm) -Newtonians) were distributed by Celestron and Tasco. In 1993, the first refracting telescopes were produced.
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Astronomical programs are delivered with an optomechanical Spitz A3P star machine, a full-dome digital projection system running UniView® software, surround sound, and programmable LRGB LED lighting. The planetarium is home to the Darling telescope, a 9-inch refracting telescope that belonged to John H. Darling.
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Refracting designs include achromatic and apochromatic types. Some reflecting types are Newtonian, Schmidt–Cassegrain, Maksutov-Cassegrain, and Maksutov-Newtonian. Even sophisticated designs, such as the Ritchey–Chrétien and (corrected) Dall–Kirkham, which have traditionally been the preserve of large professional-grade instruments, have become available to amateurs.
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The Nice Observatory () is an astronomical observatory located in Nice, France on the summit of Mount Gros. The observatory was founded in 1879, by the banker Raphaël Bischoffsheim. The architect was Charles Garnier, and Gustave Eiffel designed the main dome. In 1886 the largest refracting (i.e.
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The observatory moved along with the library, a purpose-built observatory being built on the library roof and a brass refracting telescope was obtained by the observatory curator Ex-Baillie James Lewis for the sum of £500. The original Dr Reid telescope was also brought from the old observatory.
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"Fluorite Refracting Telescopes". The company's name would become synonymous with the use of this type of crystal. In recent years however, Takahashi has produced some telescopes using extra-low dispersion ("ED") FPL-53 glassFPL-53 is a type of glass manufactured by Ohara GmbH. "Optical Glass for Astronomical Applications".
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A refracting telescope of 1848. Fitz knew Alexander Wolcott, who was working on a speculum mirror for a Cassegrain reflector in the early 1830s. Fitz was able to obtain the half- finished blank that Wolcott had done. He then completed the mirror in 1837 to make a telescope.
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Dome with refracting telescope made by Reinfelder. Due to the construction of a new road, the Placidustower was torn down in 1902.Wilhelm Schenz, 1930: Das erste Jahrhundert des Lyzeum Albertinum Regensburg (1810-1910), page 189 The government of Bavaria assigned 20,000 Mark to build a new observatory.Wilde, Sandra.
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The Admiralty approved his grant and he was offered the loan of further equipment from many sources. Robert Stephenson loaned his 140-ton yacht "Titania" for the expedition. Mr. Hugh Pattinson loaned his refracting telescope of . This was a Thomas Cooke equatorial with setting circles and a driving clock.
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This project was finally cancelled. The square was redeveloped in 1994-1995, during which an underground parking lot was dug. Within the square, a kind of refracting telescope provides a kaleidoscope view of the car park below. The square has had almost the same appearance since the eighteenth century.
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The renovated Grande Coupole Meudon Great Refractor (also known as the Grande Lunette) is a double telescope with lenses (83 cm + 62 cm), in Meudon, France. It is a twin refracting telescope built in 1891, with one visual and one photographic, on a single square-tube together on an equatorial mount, inside a dome. The Refractor was built for the Meudon Observatory, and is the largest double doublet (twin achromat) refracting telescope in Europe, but about the same size as several telescopes in this period, when this style of telescope was popular. Other large telescopes of a similar type include the James Lick telescope (91.4), Potsdam Great Refractor (80+50 cm), and the Greenwich 28 inch refractor (71.1 cm).
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Few people have a pair of eyes that show exactly equal refractive characteristics; one eye may need a "stronger" (i.e. more refracting) lens than the other. Corrective lenses bring the image back into focus on the retina. They are made to conform to the prescription of an ophthalmologist or optometrist.
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Eyepieces are optical systems where the entrance pupil is invariably located outside of the system. They must be designed for optimal performance for a specific distance to this entrance pupil (i.e. with minimum aberrations for this distance). In a refracting astronomical telescope the entrance pupil is identical with the objective.
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RIT owns a 12" Meade telescope, a 16" telescope, and several smaller refracting telescopes. In addition, a two-element radio interferometer based on the SIMPLE design is being constructed and will be used as a teaching instrument to expose students in astronomy labs to observations at other wavelengths. RIT 2017.
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Jin, Z., T.P. Charlock, K. Rutledge, K. Stamnes, and Y. Wang, An analytical solution of radiative transfer in the coupled atmosphere-ocean system with rough surface. Appl. Opt., 45, 7443-7455, 2006. Jin, Z., and K. Stamnes, Radiative transfer in nonuniformly refracting layered media: atmosphere-ocean system, Appl. Opt., 33, 431-442, 1994.
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Yerkes Observatory's 40-inch (~102 cm) refracting telescope has a doublet lens produced by the optical firm Alvan Clark & Sons and a mounting by the Warner & Swasey Company. It was the largest refracting telescope used for astronomical research. In the years following its establishment, the bar was set and tried to be exceeded; an even larger demonstration refractor, the Great Paris Exhibition Telescope of 1900, was exhibited at the Paris Universal Exhibition of 1900. (However, this was not much of a success and was dismantled, and it did not become part of an active University observatory.) The mounting and tube for the 40-inch telescope was exhibited at the 1893 World's Columbian Exposition in Chicago before being installed in the observatory.
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This led opticians to experiment with lenses constructed of more than one type of glass in an attempt to canceling the errors produced by each type of glass. It was hoped that this would create an "achromatic lens"; a lens that would focus all colors to a single point, and produce instruments of much shorter focal length. The first person who succeeded in making a practical achromatic refracting telescope was Chester Moore Hall from Essex, England. He argued that the different humours of the human eye refract rays of light to produce an image on the retina which is free from color, and he reasonably argued that it might be possible to produce a like result by combining lenses composed of different refracting media.
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The idea that the objective, or light-gathering element, could be a mirror instead of a lens was being investigated soon after the invention of the refracting telescope. The potential advantages of using parabolic mirrors—reduction of spherical aberration and no chromatic aberration—led to many proposed designs and several attempts to build reflecting telescopes.Attempts by Niccolò Zucchi and James Gregory and theoretical designs by Bonaventura Cavalieri, Marin Mersenne, and Gregory among others In 1668, Isaac Newton built the first practical reflecting telescope, of a design which now bears his name, the Newtonian reflector. The invention of the achromatic lens in 1733 partially corrected color aberrations present in the simple lens and enabled the construction of shorter, more functional refracting telescopes.
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A Troughton refracting telescope of 2.5 inch aperture was installed in a dome in 1795. The telescope was manufactured by J & E Troughton of London, and is noted for its late 18th century brass metal work. This is also called the Troughton Equatorial Telescope, for having an equatorial mounting. The observatory had an Earnshaw Regulator.
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Nothing Sacred is a play by Canadian playwright George F. Walker, written as a stage adaptation of Ivan Turgenev's 1862 novel Fathers and Sons."Refracting Russia Through the Present". Newsday, October 23, 1992. The play received its first production at Toronto, Ontario's CentreStage in the 1987-88 season, under the direction of Bill Glassco.
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English translation: Experiments with the double refracting Iceland crystal which led to the discovery of a marvelous and strange refraction, tr. by Werner Brandt. Westtown, Pa., 1959. He published an accurate description of the phenomenon, but since the physical nature of light was poorly understood at the time, he was unable to explain it.
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The ocular opening is on the side of the device in the declination axis at viewing height. Data: 900 mm clear aperture, 9000 mm focal width, with a 5940 mm reducer. The second instrument is a Takahashi type FS-15, which is a classic refracting telescope. The instrument is particularly suitable for planetary observations.
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John Flamsteed's mural arc. The telescope was mounted on a frame with a radius of about 2 metres. It was attached to a wall aligned to the meridian. There was rackwork and a micrometer, which are not shown In 1608 a patent was submitted to the government in the Netherlands for a refracting telescope.
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Engraved illustration of a focal length Keplerian astronomical refracting telescope built by Johannes Hevelius. The Keplerian telescope, invented by Johannes Kepler in 1611, is an improvement on Galileo's design. It uses a convex lens as the eyepiece instead of Galileo's concave one. The advantage of this arrangement is that the rays of light emerging from the eyepiece are converging.
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Sterling, "Dr Jekyll and Mr Jackass: Fight Club as a refraction of Hogg's Justified Sinner and Stevenson's Dr Jekyll and Mr Hyde", in S. O. Jaén and C. Gutleben, eds, Refracting the Canon in Contemporary British Literature and Film (Amsterdamn: Rodopi, 2004), , p. 84. Hamlet (2000), American Psycho (2000), Underworld (2003), The Machinist (2004) and Darling (2015).
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Tebbutt was acknowledged as the first discoverer of this comet, and the first to compute its approximate orbit. In November 1861 he purchased an excellent refracting telescope of aperture and focal length. In 1862, on the resignation of the Rev. W. Scott, he was offered the position of government astronomer for New South Wales but refused it.
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Contact lenses made from these materials are called rigid gas permeable lenses or 'RGPs'. A rigid lens is able to cover the natural shape of the cornea with a new refracting surface. This means that a spherical rigid contact lens can correct corneal astigmatism. Rigid lenses can also be made as a front-toric, back-toric, or bitoric.
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He measured the diameter of the pupil of a dark-adapted eye to be 1/3 inch (8mm), which was larger than the figure that was believed at that time. Steavenson also studied the optics of telescopes. He assessed the image quality provided by several large refracting telescopes. Steavenson became noted as a historian of astronomy.
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The observatory is located on the northernmost point of the Baldwin Wallace University campus. Built in 1940, the observatory is named after Katherine Ward Burrell as a memorial to her late husband Edward P. Burrell. The observatory houses a Warner & Swasey refracting telescope with a 13-inch objective, a 4-inch finder, and a 1-inch finder.
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It was of the largest refracting telescopes in Europe, and was active for a century until 1991. In the 21st century it was renovated and supports public education and visitation. The Meudon refractor was built at Meudon Observatory. It is one of three sites of the Paris Observatory; Meudon Observatory became part of the Paris Observatory in 1926.
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When a wavefront is refracted from one medium to another, the incident (incoming) and refracted (outgoing) portions of the wavefront meet at a common line on the refracting surface (interface). Let this line, denoted by L, move at velocity across the surface,Cf. Born & Wolf, 1970, pp.12–13. where is measured normal to L (Fig.4).
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It has a yellow or white streak and a yellow, green, brown or red color. Its lustre is adamantine, vitreous and resinous, and it has conchoidal, brittle and sectile fracture. Pharmacosiderite has an isometric crystal system, with yellowish-green, sharply defined cube crystals. Its crystals are doubly refracting, and exhibit a banded structure in polarized light.
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General Optical sold out to Shuron Optical of Geneva, NY in 1927, which sold the refractor until the late 1930s. A refined and improved version of the Genothalmic Refractor was manufactured in London starting around 1932, and sold in the UK by S. R. Stearman, S. Pulzer & Son Ltd., and others, as the British Refracting Unit (B.R.U.).
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Rutgers equipped the observatory with "a 6.5-inch equatorial refracting telescope, a meridian circle with four-inch object glass for transit observations, a sidereal clock, a mean solar clock...chronograph, repeating circle, and other instruments."Murray, David. Hand-Book of the Grounds and Buildings and the Memorials, Portraits and Busts of Rutgers College. Rutgers College Publication No. 11.
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One of the really famous applications of refracting telescope, was when Galileo used it for astronomy; he discovered the four largest moons of Jupiter in 1609. Furthermore, early refractors were also used to discover the largest moon of Saturn, Titan, several decades later as well as three more of Saturn's moons. In the 19th century, refracting telescopes were used for pioneering work on astrophotography and spectroscopy, and the related instrument, the heliometer, was used to calculate the distance to another star for the first time. There modest apertures did not lead to as many discoveries and typically so small in aperture many astronomical objects were simply not observeable until the advent of long-exposure photograph, by which time the reputation and quirks of reflecting telescopes was beginning to exceed those of the refractors.
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Percival Lowell in 1914, observing Venus in the daytime with the Alvan Clark & Sons refracting telescope at Flagstaff, Arizona Although Lowell was better known for his observations of Mars, he also drew maps of the planet Venus. He began observing Venus in detail in mid-1896 soon after the Alvan Clark & Sons refracting telescope was installed at his new Flagstaff, Arizona observatory. Lowell observed the planet high in the daytime sky with the telescope's lens stopped down to 3 inches in diameter to reduce the effect of the turbulent daytime atmosphere. Lowell observed spoke-like surface features including a central dark spot, contrary to what was suspected then (and known now): that Venus has no surface features visible from Earth, being covered in an atmosphere that is opaque.
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The observatory is equipped with a large refracting telescope made by John Brashear. That telescope is no longer functional, but there is a more modern Celestron C11 reflecting telescope that is used by students. Two levels below are the E. Howard & Co. Style No. 3 clock works. Alongside the clock is an enormous bronze bell by the Meneely Bell Foundry.
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Modern Fresnel lenses usually consist of all refractive elements. However many of the lighthouses have both refracting and reflecting elements, as shown in the photographs and diagram. That is, the outer elements are sections of reflectors while the inner elements are sections of refractive lenses. Total internal reflection was often used to avoid the light loss in reflection from a silvered mirror.
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An American, Thomas Godfrey, independently invented the octant at approximately the same time. Hadley also developed ways to make precision aspheric and parabolic objective mirrors for reflecting telescopes. In 1721 he showed the first parabolic Newtonian telescope to the Royal Society.amazing-space.stsci.edu - Hadley’s Reflector This Newtonian, with a primary mirror, compared favorably with the large aerial refracting telescopes of the day.
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The image of a star can appear blue on one side and orange on the other. Early refracting telescopes with non-achromatic objectives were constructed with very long focal lengths to mask the chromatic aberration. An Achromatic telescope uses an achromatic lens to correct for this. An achromatic lens is a compound lenses made with two types of glass with different dispersion.
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In 1878, the University of Virginia officially received McCormick's donation of the telescope. This was followed in 1881 by a donation of $18,000 for the observatory itself, contingent on the University's raising the funds to endow the professorship. The 65 cm refracting telescope was made by Alvan Clark & Sons of Cambridgeport, Massachusetts, who were regarded as the finest telescope makers of the age.
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All frequencies in the HF spectrum (3–30 MHz) can be refracted by charged ions in the ionosphere. Refracting signals off the ionosphere is called skywave propagation, and the operator is said to be "shooting skip". CB operators have communicated across thousands of miles and sometimes around the world. Even low-power 27 MHz signals can sometimes propagate over long distances.
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Smith Observatory and Dr. William R. Brooks House is a historic home and observatory located at Geneva in Ontario County, New York. Both structures were built in 1888. The observatory is a small frame building consisting of a two-story tower flanked by two small wings. The tower contains a 10-inch refracting telescope by Warner & Swasey of Cleveland, Ohio.
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Ears Like Golden Bats is the third album by My Teenage Stride. Lawrence Lui of CokemachineGlow.com gave it a 69% rating, stating "taking C86 pastoralism and refracting it through the prism of ‘90s lo-fi Amer-indie, Ears Like Golden Bats projects a treble-happy modesty that can be at once charming and cloying". Jennifer Kelly of PopMatters described it as "wonderful stuff".
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Binoculars with high magnification and heavy weight usually require some sort of mount to stabilize the image. A magnification of 10x is generally considered the practical limit for observation with handheld binoculars. Binoculars more powerful than 15×70 require support of some type. Much larger binoculars have been made by amateur telescope makers, essentially using two refracting or reflecting astronomical telescopes.
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Roberto Zaldivar is an Argentine doctor who is one of the foremost ophthalmologists and refracting surgeons in the world. He is credited for several breakthroughs in the use of lasers to correct visual impairments. His latest breakthrough is a new technique called bioptics, a term he introduced. He practices medicine out of his own Instituto Zaldivar, located in the Argentine city of Mendoza.
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These chromatic aberrations are bad because they create differences in focus, which prevent good resolution; however, if the range is restricted it is possible to achieve good resolution. Furthermore, chromatic aberrations can be corrected by using two or more refracting materials over the full visible range. It is harder to correct chromatic aberrations over wider spectral ranges without further optical complexity.
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The dome received a refracting telescope build by Reinfelder. In the year 1919 physicist Professor Karl Stoeckl was appointed to the Lyzeum in Regensburg. In November 1919, a local newspaper announced a public talk about the Milky Way for the first Thursday in the new year.Regensburger Anzeiger, 10 November 1919 Since then Karl Stoeckl regularly opened the observatory to the public.
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It was modeled after the Goodsell Observatory at Carleton College in Northfield, Minnesota, and constructed from rusticated red sandstone blocks. The Romanesque structure includes a central rotunda and domed roof. Construction began in 1890. The 20-inch objective lens for the observatory's main refracting telescope was made by Alvan Clark & Sons, and the mount was built by George Nicholas Saegmuller.
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With optical sensor arrays, tiny lens systems serve to focus and concentrate the light onto the photo-diode surface, instead of allowing it to fall on non-photosensitive areas of the pixel device. Fill- factor is the ratio of the active refracting area, i.e. that area which directs light to the photo-sensor, to the total contiguous area occupied by the microlens array.
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The James Richard Jewett Observatory is an astronomical observatory owned and operated by Washington State University. It is located in Pullman, Washington (US). It houses the largest refracting telescope in the state of Washington. The 12-inch lens was originally ground and polished between 1887 and 1889 by Alvan Clark & Sons for an amateur astronomer, who died before the telescope could be assembled.
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Winthrop's collection of books he brought back to America was remarkable. He is credited as being the first chemist and metallurgist in the American colonies while he practiced alchemy and medicine. Winthrop also studied astronomy with his foot refracting telescope. In 1664, he wrote a letter to Sir Robert Moray regarding a "fifth satellite of Jupiter" that he believed he observed.
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The University of Alabama Observatory is an astronomical observatory owned and operated by the University of Alabama in Tuscaloosa, Alabama. The new domed observatory was built atop Gallalee Hall, completed in 1949. It replaced the Old Observatory, which had been in use from 1849 until the 1890s. Initially equipped with a refracting telescope, this was the university's primary telescope from 1950 until 2004.
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At the start of the 19th century, improvements in the size and quality of telescope optics proved a significant advance in observation capability. Most notable among these enhancements was the two-component achromatic lens of the German optician Joseph von Fraunhofer that essentially eliminated coma—an optical effect that can distort the outer edge of the image. By 1812, Fraunhofer had succeeded in creating an achromatic objective lens in diameter. The size of this primary lens is the main factor in determining the light gathering ability and resolution of a refracting telescope. During the opposition of Mars in 1830, the German astronomers Johann Heinrich Mädler and Wilhelm Beer used a Fraunhofer refracting telescope to launch an extensive study of the planet. They chose a feature located 8° south of the equator as their point of reference.
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The "onion" dome at the Royal Observatory, Greenwich housing a 28-inch refracting telescope with a remaining segment of William Herschel's 120-centimetre (47 in) diameter reflecting telescope (called the "40-foot telescope" due to its focal length) in the foreground. The earliest existing record of a telescope was a 1608 patent submitted to the government in the Netherlands by Middelburg spectacle maker Hans Lippershey for a refracting telescope. galileo.rice.edu The Galileo Project > Science > The Telescope by Al Van Helden: The Hague discussed the patent applications first of Hans Lipperhey of Middelburg, and then of Jacob Metius of Alkmaar... another citizen of Middelburg, Zacharias Janssen is sometimes associated with the invention The actual inventor is unknown but word of it spread through Europe. Galileo heard about it and, in 1609, built his own version, and made his telescopic observations of celestial objects.
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The other surface is shaped by the container that holds the molten glass acting as a mould. Lenses made this way are sometimes used as objectives in refracting telescopes. The axis of rotation becomes the axis of the paraboloid. It is not necessary for this axis to be in the centre of the container of glass, or even for it to pass through the container.
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Dr. Thomas Reid, an eminent Glasgow oculist, donated a brass- bodied, refracting telescope to the town, and it was housed in the library. He also donated the sum of £35 to convert a top-floor room, where a dome was built on the roof of the building for it. Thus founding Airdrie Public Observatory. Robert Dunlop was the first Honorary Curator, followed shortly by Mr Peter Scotland.
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At the time this was the largest instrument in the German Empire. In 1881, the ninth General Assembly of the Astronomische Gesellschaft met in Strasbourg to mark the official inauguration. The refracting telescope inside the dome The observatory site was selected primarily for instruction purposes and political symbolism, rather than the observational qualities. It was a low-lying site that was prone to mists.
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According to Pevsner, the main school building dates to c. 1770, built by the family of Admiral Edward Vernon. It was acquired by Colonel George Tomline in 1848, who proceeded to extend and modify the building and grounds. Most notably, this included the addition of an observatory containing a 26 cm refracting telescope, known as the Tomline Refractor, that is still in use today.
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The Greek Revival-style observatory building was completed in 1844, though the equatorial mounted Troughton & Simms refracting telescope was not mounted until 1849. The observation room was built with a large central section, capped by a revolving diameter dome. At the west end of the building was a transit instrument room with a north-south slit in the roof. Opposite the transit room was an office.
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On the basis of Archenhold's plans, the world's longest moving refracting telescope was built with a focal length of 21 meters. The telescope was part of the Great Industrial Exposition of Berlin. The giant telescope was constructed in Treptow, a suburb of Berlin. The telescope was opened to the public on 1 May 1896 in a temporary wooden structure which was completed in September.
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A German cannot use the word "fatherland" or the phrase "blood and soil" without (possibly unintentionally) also echoing (or, Bakhtin would say "refracting") the meaning that those terms took on under Nazism. Every word has a history of usage to which it responds, and anticipates a future response. The term 'dialogic' does not only apply to literature. For Bakhtin, all language—indeed, all thought—appears as dialogical.
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In 1874, he prepared several expeditions to monitor the transit of Venus across the solar disk in eastern Asia, Caucasus, Persia and Egypt. In 1887, he sent several groups within Russia to observe the solar eclipse. In some of those expeditions, he took part personally. In 1885, a 30-inch refracting telescope was installed at Pulkovo, at the time the largest in the world (see great refractor).
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Actually, there are two kinds of matrices, viz. a refraction matrix describing the refraction at a lens surface, and a translation matrix, describing the translation of the plane of reference to the next refracting surface, where another refraction matrix applies. The optical system, consisting of a combination of lenses and/or reflective elements, is simply described by the matrix resulting from the product of the components' matrices.
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Micrograph of Melanin pigment (light refracting granular material—center of image) in a pigmented melanoma. Micrograph of the epidermis, with melanin labeled at left. Melanin (; from melas, "black, dark") is a broad term for a group of natural pigments found in most organisms. Melanin is produced through a multistage chemical process known as melanogenesis, where the oxidation of the amino acid tyrosine is followed by polymerization.
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The blink comparator is an instrument that is used to compare two nearly identical photographs made of the same section of sky at different points in time. The comparator alternates illumination of the two plates, and any changes are revealed by blinking points or streaks. This instrument has been used to find asteroids, comets, and variable stars. 50 cm refracting telescope at Nice Observatory.
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The lighthouse was initially provided with a large (first-order) fixed dioptric along with a set of mirrors (which were replaced with refracting prisms ten years later); the lens was by Isaac Cookson & co. of Newcastle upon Tyne. The lamp was oil-fuelled. In 1854 red sectors were added, to warn ships of Hauxley Point to the south and Boulmer Rocks to the north.
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The main dome houses a refractor with a diameter of and a focal length of built by the Grubb Telescope Company. At that time, it was the world's largest refracting telescope. Land for the new observatory was purchased in 1872, and was noted for having increased elevations (about 150 ft) above the city. Construction started in March 1874, and it was opened with new instruments in 1877.
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Max Waldmeier (18 April 1912 – 26 September 2000) was a Swiss astronomer, known for his research on sunspots. As director of the Zurich Observatory until 1980, Waldmeier insisted on counting sunspots by eye over automated methods, using a Fraunhofer refracting telescope installed by Zurich Observatory director Rudolf Wolf in 1849.Jonathon Keats (2015) "The 315-Year- Old Science Experiment" Nautilus, 26 March 2015. Retrieved 11 June 2016.
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Cf. pp.54-60 At 10:50 pm on the night of October 1, 1847, Mitchell discovered Comet 1847 VI (modern designation C/1847 T1) using a Dollond refracting telescope with three inches of aperture and forty-six inch focal length.Tappan, Eva March, Heroes of Progress: Stories of Successful Americans, Houghton Mifflin Company, 1921. Cf. pp.54-60AJS, 2nd Ser., v. 5, 1848, p.
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Doubly refracting mineral sections will in all cases appear black in certain positions as the stage is rotated. They are said to "go extinct" when this takes place. The angle between these and any cleavages can be measured by rotating the stage and recording these positions. These angles are characteristic of the system to which the mineral belongs, and often of the mineral species itself (see Crystallography).
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In 1837 he established his first optical business in a small shop at 50 Stonegate, York, and later moved to larger premises in Coney Street. He built his first telescope for William Gray. At that time, the excise tax on glass discouraged the making of refracting telescopes, which were usually imported from abroad. Cooke was thus one of the pioneers of making such telescopes in Britain.
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IThe Sheepshanks dome is in between the Flamsteed house (on the right), and the Great Equatorial dome on the far left (partially obscured by a tree). The Sheepshanks was operated from the Altazimuth Pavilion from 1963 to 1982. Sheepshanks equatorial was a 6.7 inch (170 mm) refracting telescope established in 1838 at the Royal Observatory in Greenwich. The telescope was donated to the observatory by Richard Sheepshanks.
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Built in 1783–1785, the observatory houses a 12-inch (30 cm) refracting telescope which was built by Grubbs of Dublin using a French manufactured lens. The 1880 Definition of Time Act set the official time in Ireland to be Dublin Mean Time. This was computed as the time at Dunsink, which was about GMT-25m21. In 1916 another Act moved Ireland to Greenwich Mean Time.
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303–04Paolini, William (2013). Choosing and Using Astronomical Eyepieces, p. 5 Huygens discovered that two air spaced lenses can be used to make an eyepiece with zero transverse chromatic aberration. These eyepieces work well with the very long focal length telescopes (in Huygens day they were used with single element long focal length non-achromatic refracting telescopes, including very long focal length aerial telescopes).
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Optical Society, 22, 235 (1921) It was repopularized in the 1980s and is now mass-produced. Amateur astronomers in particular use them to collimate reflecting or refracting telescopes.Pepin, M. B., Care of Astronomical Telescopes and Accessories, Patrick Moore’s Practical Astronomy Series, Springer-Verlag 2005, p. 164.Suiter, H. R., Star Testing Astronomical Telescopes - A Manual for Optical Evaluation and Adjustment, Willmann-Bell 1994, p. 121.
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In 1843 he published a paper on circular polarisation of light and various essential oils. His optical apparatus was innovative, and he developed a double refracting goniometer, also known as a Leeson prism. It was made from Iceland spar, and later applied to the measurement of angles in small crystals.H. B. Leeson, Observations of the Circular Polarization of Light by Transmission through Fluids, London and Edinburgh Philosophical Magazine vol.
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No telescope can form a perfect image. Even if a reflecting telescope could have a perfect mirror, or a refracting telescope could have a perfect lens, the effects of aperture diffraction are unavoidable. In reality, perfect mirrors and perfect lenses do not exist, so image aberrations in addition to aperture diffraction must be taken into account. Image aberrations can be broken down into two main classes, monochromatic, and polychromatic.
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The panels are tinted in red, white and blue, possibly refracting the byline Life magazine gave Moore's photographs, They Fight a Fire That Won't Go Out. The panels are a faithful representation of Moore's photograph, but with heightened contrast expressing a newsprint quality. Warhol used Moore's photographs without his permission, and Moore subsequently filed a lawsuit against him for copyright infringement. The case was settled out of court.
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In the mid-1980s, the corrector plate was replaced using glass with less chromatic aberration, producing higher quality images over a broader spectrum. Between 2000 and 2001, it was converted to use a CCD imager. The corrector plate was recently replaced using glass that is transparent to a wider range of wavelengths. The telescope was originally hand-guided through one of two refracting telescopes mounted on either side.
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Their chemical composition is created to take in some color of light and reflect the rest. In contrast, schematochromes (structural colors) are colors created by light reflections from a colorless surface and refractions by tissues. Schematochromes act like prisms, refracting and dispersing visible light to the surroundings, which will eventually reflect a specific combination of colors. These categories are determined by the movement of pigments within the chromatophores.
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A collimator collimates the beam that is dispersed by a refracting prism and re-imaged onto a detection system by a re- imager. Special care is taken to produce the best possible image of the source onto the slit. The purpose of the collimator and re-imaging optics are to take the best possible image of the slit. An area-array of elements fills the detection system at this stage.
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Before the advent of telescopic photography, eight moons of Saturn were discovered by direct observation using optical telescopes. Saturn's largest moon, Titan, was discovered in 1655 by Christiaan Huygens using a objective lens on a refracting telescope of his own design. Tethys, Dione, Rhea and Iapetus (the "Sidera Lodoicea") were discovered between 1671 and 1684 by Giovanni Domenico Cassini. Mimas and Enceladus were discovered in 1789 by William Herschel.
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Hunter was appointed an assistant at the Royal Observatory, Greenwich in 1937, at a time when the observatory was under the directorship of Sir Harold Spencer Jones, the Astronomer Royal. Hunter served as head of the observatory's Department of Astrometry and Astrophysics from 1937 to 1956. In 1937 he married Joan Portnell. He worked on measuring the distances of stars using photography with the Greenwich 26-inch diameter refracting telescope.
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This began with a proposal by Pendry, in 2003. Magnifying the image required a new design concept in which the surface of the negatively refracting lens is curved. One cylinder touches another cylinder, resulting in a curved cylindrical lens which reproduced the contents of the smaller cylinder in magnified but undistorted form outside the larger cylinder. Coordinate transformations are required to curve the original perfect lens into the cylindrical, lens structure.
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Conventional traffic signal lighting, still common in some areas, utilizes a standard light bulb. Typically, a 67, 69, or 115 watt medium-base (household lamp in the US) light bulb provides the illumination. Light then bounces off a mirrored glass or polished aluminium reflector bowl, and out through a polycarbonate plastic or glass signal lens. In some signals, these lenses were cut to include a specific refracting pattern.
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Vanderbilt's first observatory was housed on the campus itself. It was equipped with a refracting telescope and was the site of E. E. Barnard's earliest astronomical work. Barnard would eventually discover 16 comets and the fifth moon of Jupiter, receive the only honorary degree Vanderbilt has ever awarded, and have the on-campus observatory named in his honor. However, that on-campus observatory would eventually prove insufficient for the university's needs.
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Engraved illustration of a focal length Keplerian astronomical refracting telescope built by Johannes Hevelius. From his book, "Machina coelestis" (first part), published in 1673. The sharpness of the image in Kepler's telescope was limited by the chromatic aberration introduced by the non-uniform refractive properties of the objective lens. The only way to overcome this limitation at high magnifying powers was to create objectives with very long focal lengths.
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The Cincinnati Observatory is located in Cincinnati, Ohio (United States) on top of Mount Lookout. It consists of two observatory buildings housing an 11-inch (28 cm) and 16 inch (41 cm) aperture refracting telescope. It is the oldest professional observatory in the United States. It was a key facility for astronomical research and education at the University of Cincinnati and currently operates as a 19th-century observatory.
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The researchers played natural image movies in front of cats and used a multielectrode array to record neural signals. This was achieved by refracting the eyes of the cats and then contact lenses being fitted into them. They found that in the LGN, the natural images were decorrelated and concluded, "the early visual pathway has specifically adapted for efficient coding of natural visual information during evolution and/or development".
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The chemical experiment that tested how life originated on early Earth, the Miller–Urey experiment, was conducted at the university. REM sleep was discovered at the university in 1953 by Nathaniel Kleitman and Eugene Aserinsky. The University of Chicago (Department of Astronomy and Astrophysics) operated the Yerkes Observatory in Williams Bay, Wisconsin from 1897 until 2018, where the largest operating refracting telescope in the world and other telescopes are located.
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Alvan Clark (March 8, 1804 – August 19, 1887), born in Ashfield, Massachusetts, the descendant of a Cape Cod whaling family of English ancestry, was an American astronomer and telescope maker. He started as a portrait painter and engraver (c.1830s-1850s), and at the age of 40 became involved in telescope making. Using glass blanks made by Chance Brothers of Birmingham and Feil-Mantois of Paris, his firm Alvan Clark & Sons ground lenses for refracting telescopes, including the largest in the world at the time: the at Dearborn Observatory at the Old University of Chicago (the lens was originally intended for Ole Miss), the two telescopes at the United States Naval Observatory and McCormick Observatory, the at Pulkovo Observatory (destroyed in the Siege of Leningrad; only the lens survives), the telescope at Lick Observatory (still third-largest) and later the at Yerkes Observatory, which remains the largest successful refracting telescope in the world.
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Skywave modes of radio communication operate by bending (refracting) radio waves (electromagnetic radiation) through the Ionosphere. During the "peaks" of the solar cycle, the ionosphere becomes increasingly ionized by solar photons and cosmic rays. This affects the propagation of the radio wave in complex ways that can either facilitate or hinder communications. Forecasting of skywave modes is of considerable interest to commercial marine and aircraft communications, amateur radio operators and shortwave broadcasters.
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The crystals behave like prisms and mirrors, refracting and reflecting sunlight between their faces, sending shafts of light in particular directions. For circular halos, the preferred angular distance are 22 and 46 degrees from the ice crystals which create them. Atmospheric phenomena such as halos have been used as part of weather lore as an empirical means of weather forecasting, with their presence indicating an approach of a warm front and its associated rain.
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Baden-Powell Unilens The unilens monocular is a simple refracting telescope for field use, designed by Robert Baden-Powell. Consisting of only one lens, it is the simplest of all telescopes, and while occupying very little space can still magnify a distant image up to about four times. The nature of its operation however does not accommodate to everyone's visual acuity, with only three out of four people able to use it.
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This present campus observatory is not the first to have been built on the MSU campus. In 1880, Professor Rolla C. Carpenter built an observatory for the (then) State Agricultural College to house an Alvan Clark & Sons refracting telescope of 5.5 inches aperture. The observatory was located behind his residence at Faculty Row No.2, near where Sarah Langdon Williams Hall stands today. The original telescope is on exhibit at the Abrams Planetarium.
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In very large apertures, there is also a problem of lens sagging, a result of gravity deforming glass. Since a lens can only be held in place by its edge, the center of a large lens sags due to gravity, distorting the images it produces. The largest practical lens size in a refracting telescope is around . There is a further problem of glass defects, striae or small air bubbles trapped within the glass.
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Lens sag is a problem that sometimes afflicts very large refracting telescopes. It is the equivalent of mirror sag in reflecting telescopes. It occurs when the physical weight of the glass causes a distortion in the shape of the lens because the lens can only be supported by the edges. A mirror on the other hand can be effectively supported by the entire opposite face, making mirror sag much less of a problem.
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Angell Hall Observatory is an astronomical observatory owned and operated by University of Michigan. It is located on the UM Central Campus on top of Angell Hall in Ann Arbor, Michigan (US). It has a computer-controlled 0.4-m Cassegrain telescope in its single dome, and a small radio telescope on the roof. In the past it has housed a large, clock-driven refracting telescope and a reflecting telescope in side-by-side domes.
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Society continued its work in 1953 as the Astronomical Society Ruđer Bošković and has begun to publish magazine Vasiona. Publication of books was also one of the Society's main activities: Ruđer Bošković's Eclipses of the Sun and the Moon (translated and commented by Nenad Janković) was published. In 1964 Society has established the Public Observatory, located in the Despot's Tower in Kalemegdan. At the terrace of Observatory a Zeiss refracting telescope (110/200) is placed.
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Imaging spectrometers are used specifically for the purpose of measuring the spectral content of light and electromagnetic light. The spectral data gathered is used to give the operator insight into the sources of radiation. Prism spectrometers use a classical method of dispersing radiation by means of a prism as a refracting element. The imaging spectrometer works by imaging a radiation source onto what is called a “slit” by means of a source imager.
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Catadioptric systems are used in Imagine Spectrometers and are compact, too; however, the collimator or imager will be made up of two curved mirrors and three refracting elements, and thus, the system is very complex. Optical complexity is unfavorable, however, because effects scatter all optical surfaces and stray reflections. Scattered radiation can interfere with the detector by entering into it and causing errors in recorded spectra. Stray radiation is referred to as stray light.
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This minor planet is named for the two brothers Paul Henry and Prosper Henry (1848–1905 and 1849–1903, respectively), who each discovered seven asteroids. As opticians, they constructed the 76-cm refracting telescope at Nice Observatory, among others. While mapping the ecliptic during their Carte du Ciel survey, they made all their fourteen, low-numbered asteroid discoveries, starting with 125 Liberatrix. The Henry Brothers are also honored by the lunar crater Henry Frères.
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The observatory also holds a collection of over 170,000 photographic plates. The Yerkes 40-inch was the largest refracting-type telescope in the world when it was dedicated although there had been several larger reflecting telescopes. During this time, there were many questions about the merits of the various materials used to construct and design telescopes. Another large telescope of this period was the Great Melbourne Telescope, which was also a reflector.
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Early depiction of a "Dutch telescope" from 1624. The history of the telescope can be traced to before the invention of the earliest known telescope, which appeared in 1608 in the Netherlands, when a patent was submitted by Hans Lippershey, an eyeglass maker. Although Lippershey did not receive his patent, news of the invention soon spread across Europe. The design of these early refracting telescopes consisted of a convex objective lens and a concave eyepiece.
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In some of the very long refracting telescopes constructed after 1675, no tube was employed at all. The objective was mounted on a swiveling ball-joint on top of a pole, tree, or any available tall structure and aimed by means of string or connecting rod. The eyepiece was handheld or mounted on a stand at the focus, and the image was found by trial and error. These were consequently termed aerial telescopes.
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The sniper and spotter use a wide variety of optics, such as the sniper scope, spotter weapon scope,nowadays in modern warfare there are several improvements in the field of computerised optic and manual optics .A range of devices are used to accurately mark an enemy .it has become a trend to use high caliber rifles . A telescopic sight, commonly called a scope, is an optical sighting device that is based on a refracting telescope.
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Built in 1900 and dedicated on May 15, 1901, the observatory was thoroughly renovated during the 2001–02 academic year. Although the facility is no longer used for research, its original refracting telescope, built by Warner & Swasey Company with a 12-inch (0.3-meter) Brashear objective lens, also received a complete restoration. The telescope is now used regularly for outreach events and undergraduate-level classes. Kirkwood Observatory also has an instructional solar telescope.
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"Merz and Mahler" refracting telescopefrom "Smith's Illustrated Astronomy", 1848 Cincinnati Observatory was built by Ormsby M. Mitchel at the peak of Mount Ida, a hill that overlooks downtown Cincinnati. Nicholas Longworth donated of land for the purpose. The Holy Cross Monastery and Chapel stands today at the site. The cornerstone was laid on November 9, 1843, and presiding over the occasion was former President John Quincy Adams, with an introduction by Judge Jacob Burnet.
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Bose wrote in a Bengali essay, "Adrisya Alok" ("Invisible Light"), "The invisible light can easily pass through brick walls, buildings etc. Therefore, messages can be transmitted by means of it without the mediation of wires." Bose's first scientific paper, "On polarisation of electric rays by double-refracting crystals" was communicated to the Asiatic Society of Bengal in May 1895. Following that, Bose produced a series of articles in English, one after another.
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On January 31, 1862, American telescope-maker and astronomer Alvan Graham Clark first observed the faint companion, which is now called Sirius B, or affectionately "the Pup". This happened during testing of an aperture great refractor telescope for Dearborn Observatory, which was one of the largest refracting telescope lens in existence at the time, and the largest telescope in the United States. Sirius B's sighting was confirmed on March 8, 1862, with smaller telescopes.
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As the objective diameter of these refracting telescopes was increased to gather more light and resolve finer detail they began to have focal lengths as long as 150 feet. Besides having very long tubes, these telescopes needed scaffolding or long masts and cranes to hold them up. Their value as research tools was minimal since the telescope's support frame and tube flexed and vibrated in the slightest breeze and sometimes collapsed altogether.
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Four bee families (Andrenidae, Colletidae, Halictidae, and Apidae) contain some species that are crepuscular. Most are tropical or subtropical, but some live in arid regions at higher latitudes. These bees have greatly enlarged ocelli, which are extremely sensitive to light and dark, though incapable of forming images. Some have refracting superposition compound eyes: these combine the output of many elements of their compound eyes to provide enough light for each retinal photoreceptor.
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The Pleiades Star Cluster photographed with a 6 megapixel DSLR connected to an 80mm refracting telescope piggybacked on a larger telescope. Image is made from seven 180 second images combined and processed in Photoshop with a noise reduction plugin. Both digital camera images and scanned film images are usually adjusted in image processing software to improve the image in some way. Images can be brightened and manipulated in a computer to adjust color and increase the contrast.
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Illusion optics was recorded in 1968 when Soviet physicist Victor Veselago discovered that he can make objects appear in different areas through negatively refracting flat slab. When light is negatively refracted, the light is directed towards the direction it entered and deflected away from the line of refraction. Normal refraction occurs when light passes through the line of refraction. Veselago used this theory to work the slab into a lens, which he recorded in his experiments.
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The Planetarium's 23-meter dome can seat some four hundred spectators viewing projections of the sky from both analogue and digital planetarium projectors. It hosts regular public shows on astronomical topics as well as a variety of other events. In 2011 it hosted the fifth International Olympiad on Astronomy and Astrophysics. The Planetarium's sister astronomical observatory is equipped with a 300-mm diameter refracting telescope (the largest refractor in use in Poland) and a number of smaller instruments.
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The telescope converts a bundle of parallel rays to make an angle α, with the optical axis to a second parallel bundle with angle β. The ratio β/α is called the angular magnification. It equals the ratio between the retinal image sizes obtained with and without the telescope.Stephen G. Lipson, Ariel Lipson, Henry Lipson, Optical Physics 4th Edition, Cambridge University Press, Refracting telescopes can come in many different configurations to correct for image orientation and types of aberration.
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Despite this some discoveries include the Moons of Mars, a fifth Moon of Jupiter, and many double star discoveries including Sirius (the Dog star). Refactors were often used for positional astronomy, besides from the other uses in photography and terrestrial viewing. Singlets The Galilean moons and many other moons of the solar system, were discovered with single-element objectives and aerial telescopes. Galileo Galilei's discovered the Galilean satellites of Jupiter in 1610 with a refracting telescope.
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In 1904, one of the discoveries made using Great Refractor of Potsdam (a double telescope with two doublets) was of the interstellar medium. The astronomer Professor Hartmann determined from observations of the binary star Mintaka in Orion, that there was the element calcium in the intervening space. ;Triplets Planet Pluto was discovered by looking at photographs (i.e. 'plates' in astronomy vernacular) in a blink comparator taken with a refracting telescope, an astrograph with a 3 element 13-inch lens.
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The basic scheme is that the primary light-gathering element, the objective (1) (the convex lens or concave mirror used to gather the incoming light), focuses that light from the distant object (4) to a focal plane where it forms a real image (5). This image may be recorded or viewed through an eyepiece (2), which acts like a magnifying glass. The eye (3) then sees an inverted magnified virtual image (6) of the object. Keplerian refracting telescope.
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Eight-inch refracting telescope at Chabot Space and Science Center Design specifications relate to the characteristics of the telescope and how it performs optically. Several properties of the specifications may change with the equipment or accessories used with the telescope; such as Barlow lenses, star diagonals and eyepieces. These interchangeable accessories don't alter the specifications of the telescope, however they alter the way the telescopes properties function, typically magnification, apparent field of view (FOV) and actual field of view.
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With photon mapping, light packets called photons are sent out into the scene from the light sources. Whenever a photon intersects with a surface, the intersection point and incoming direction are stored in a cache called the photon map. Typically, two photon maps are created for a scene: one especially for caustics and a global one for other light. After intersecting the surface, a probability for either reflecting, absorbing, or transmitting/refracting is given by the material.
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Stereoptic depth perception obtained from two dimensional red and blue or red and green images is believed to be caused primarily by optical chromatic aberrations. Chromatic aberrations are defined as types of optical distortions that occur as a consequence of refracting properties of the eye. However, other [optical] factors, image characteristics, and perceptual factors also play a role in color depth effects under natural viewing conditions. Additionally, texture properties of the stimulus can also play a role.
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In 1655, Huygens proposed that Saturn was surrounded by a solid ring, "a thin, flat ring, nowhere touching, and inclined to the ecliptic." Using a 50 power refracting telescope that he designed himself, Huygens also discovered the first of Saturn's moons, Titan.Ron Baalke, Historical Background of Saturn's Rings In the same year he observed and sketched the Orion Nebula. His drawing, the first such known of the Orion nebula, was published in Systema Saturnium in 1659.
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The Craig telescope was a large telescope built in the 1850s, and while much larger than previous refracting telescopes, it had some problems that hampered its use. Its unique design and potential caused a great deal of excitement in its day. The telescope was ready in August 1852 and was visited by William Parsons, 3rd Earl of Rosse, famous for the Leviathan of Parsonstown, a reflecting telescope and the largest telescope of this age with a six foot mirror.
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This is due to double refraction as the light bends twice, when entering and leaving the prism. With this double refraction, the two subsidiary images appear as one above and one below the main image. The distance of the two subsidiary images from the main image corresponds to the Newtonians' dispersion. The wideness or narrowness of the colored bands are, however, nonessential properties that differ according to the type of light-refracting substance that is used.
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At the time, the fused quartz gyroscopes created for Gravity Probe B were the most nearly perfect spheres ever created by humans. The gyroscopes differ from a perfect sphere by no more than 40 atoms of thickness. One is pictured here refracting the image of Albert Einstein in background. thumb The Gravity Probe B experiment comprised four London moment gyroscopes and a reference telescope sighted on HR8703 (also known as IM Pegasi), a binary star in the constellation Pegasus.
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Fitz pioneered techniques of correcting poor quality glass which made him one of the first important American telescope makers. He was the first American to make very large professional refracting telescopes.The Observatory, 1888: Henry Fitz, of New York, is credited with being the first American who obtained special distinction for the manufacture of refractors; he constructed 30 with object-glasses varying from 6 to in diameter. Fitz made the largest refractor telescopes in America, five different times.
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Ludwig Ignaz Schupmann (23 January 1851 in Geseke (Westphalia), Germany – 2 October 1920 also in Geseke) was a German professor of architecture and an optical designer. He is principally remembered today for his Medial and Brachymedial telescopes, types of catadioptric reflecting-refracting telescopes with Mangin mirrors that eliminate chromatic aberrations while using common optical glasses. Used in early lunar studies, they are used now in double-star work. The asteroid 5779 Schupmann is named in his honour.
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The astronomical collaboration between Edward and his father began with the inauguration of a newly built observatory including a sixteen-inch refracting telescope in 1883. In the following years, many of Lewis Swift's publications are brief references to Edward. Most notably, Edward discovered 25 new NGC-objects, 22 new IC-objects, multiple comets and a total of 46 nebulae. He also followed in his father's footsteps by co-discovering the periodic comet 54P/de Vico-Swift- NEAT.
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In 1937 he made the science fiction movie, Weltraumschiff I startet [Space Ship I Launches], a story about a first Moon flight which he dated on 13 June 1963, his 60th birthday. Kutter was awarded two golden medals at the Venice Biennale. Already at age 12, Kutter manufactured his first refracting telescope from lenses taken from a toy cinematograph. Later he became known to Anton Staus (1872-1955) who introduced him to the theory of 's "Brachy" telescopes.
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Markree Castle Markree Castle is a castle located in Collooney, County Sligo, Ireland. It is the ancestral seat of the Cooper family, partially moated by the River Unshin. Today it is a small family-run hotel. In the 1830s the Observatory on the grounds of the Castle had the largest refracting telescope in the world, and what today is known as the asteroid 9 Metis was discovered there in the 1840s by the Coopers' observatory staff.
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Objective lenses of binoculars In a telescope the objective is the lens at the front end of a refracting telescope (such as binoculars or telescopic sights) or the image-forming primary mirror of a reflecting or catadioptric telescope. A telescope's light- gathering power and angular resolution are both directly related to the diameter (or "aperture") of its objective lens or mirror. The larger the objective, the dimmer the object it can view and the more detail it can resolve.
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Light path through an achromatic lens. From the time of the invention of the first refracting telescopes it was generally supposed that chromatic errors seen in lenses simply arose from errors in the spherical figure of their surfaces. Opticians tried to construct lenses of varying forms of curvature to correct these errors. Isaac Newton discovered in 1666 that chromatic colors actually arose from the un-even refraction of light as it passed through the glass medium.
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At the time, African Americans were not allowed to attend the university. In the 1940s, Loper painted mostly landscapes and cityscapes of his neighborhood in Wilmington, in vivid colors. By the early 1950s, with a growing appreciation of the works of Pablo Picasso, Loper had transitioned from creating self- described mood paintings to concentrating on color and shapes, including experimenting with a kind of kaleidoscopic cubism, refracting subjects into planes as if seen through shards of glass.
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This is known as Newton's theory of colour. From this work he concluded that any refracting telescope would suffer from the dispersion of light into colours. The interest of the Royal Society encouraged him to publish his notes On Colour (later expanded into Opticks). Newton argued that light is composed of particles or corpuscles and were refracted by accelerating toward the denser medium, but he had to associate them with waves to explain the diffraction of light.
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The photoelastic phenomenon was first discovered by the Scottish physicist David Brewster.D. Brewster, Experiments on the depolarization of light as exhibited by various mineral, animal and vegetable bodies with a reference of the phenomena to the general principle of polarization, Phil. Tras. 1815, pp. 29–53.D. Brewster, On the communication of the structure of doubly-refracting crystals to glass, murite of soda, flour spar, and other substances by mechanical compression and dilation, Phil. Tras. 1816, pp. 156–178.
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These include telescopes, microscopes, pneumatic and electrostatic devices, instruments for cartographic surveys of the 18th-19th century. The dome with the 8-inch refracting telescope which Schiaparelli had installed in 1875 is also part of the Museum. Schiaparelli used this telescope for his astronomical researches of binary stellar systems, comets, asteroids and planets of the Solar System, and particularly Mars. In 1999 the telescope and the dome were fully restored to be operational, and are open to the public.
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The Great Paris Exhibition Telescope of 1900, with an objective lens of in diameter, was the largest refracting telescope ever constructed. It was built as the centerpiece of the Paris Universal Exhibition of 1900. Its construction was instigated in 1892 by François Deloncle (1856–1922), a member of the French Chambre des Députés. Since it was built for exhibit purposes within a large metropolis, and its design made it difficult to aim at astronomical objects, it was not suited for scientific use.
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Ernst Abbe (1840–1905), working for Carl Zeiss AG in Jena, Germany in the late 19th century, was the first to develop a laboratory refractometer. These first instruments had built-in thermometers and required circulating water to control instrument and fluid temperatures. They also had adjustments for eliminating the effects of dispersion and analog scales from which the readings were taken. In the Abbe' refractometer the liquid sample is sandwiched into a thin layer between an illuminating prism and a refracting prism.
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The glory can only be seen when the observer is directly between the sun and cloud of refracting water droplets. Hence, it is commonly observed while airborne, with the glory surrounding the airplane's shadow on clouds (this is often called The Glory of the Pilot). Glories can also be seen from mountains and tall buildings, when there are clouds or fog below the level of the observer, or on days with ground fog. The glory is related to the optical phenomenon anthelion.
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These transparent walls gave the illusion of looking through an actual 'soap bubble' by refracting light to obtain a rainbow-like effect for the riders inside. It was originally part of the Washington State Coliseum (now a sports venue known as Climate Pledge Arena), where it lifted 100 passengers at a time up one floor through a structure of interlocking aluminum cubes to the "World of Tomorrow" exhibit. T. C. Howard of Synergetics, Inc. designed the Bubbleator and the exhibit.
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This minor planet was named after the city of Hanoi, capital of Vietnam, which the discoverer visited in 1997. Together with astronomer Yoshihide Kozai, after whom the minor planet 3040 Kozai is named, he assisted local astronomers install a Schmidt-Cassegrain and a refracting telescope at HNUE. The installed instrumentation was funded by the Japanese Sumitomo Foundation, with the intention to foster Vietnamese astronomical research. The official naming citation was published by the Minor Planet Center on 2 February 1999 ().
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Fresnel lighthouse lenses are ranked by order, a measure of refracting power, with a first order lens being the largest, most powerful and expensive; and a sixth order lens being the smallest. The order is based on the focal length of the lens. A first order lens has the longest focal length, with the sixth being the shortest. Coastal lighthouses generally use first, second, or third order lenses, while harbor lights and beacons use fourth, fifth, or sixth order lenses.
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Catadioptric dialytes are the earliest type of catadioptric telescope. They consist of a single-element refracting telescope objective combined with a silver-backed negative lens (similar to a Mangin mirror). The first of these was the Hamiltonian telescope patented by W. F. Hamilton in 1814. The Schupmann medial telescope designed by German optician Ludwig Schupmann near the end of the 19th century placed the catadioptric mirror beyond the focus of the refractor primary and added a third correcting/focusing lens to the system.
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It has its devoted supporters and detractors. What has received attention is his notion that there is always an asymmetry between institutions and their subjects and an ever-present recoiling and refracting agency in people: a source of creativity, dissonance and resistance. As a president-elect of the South African Sociological Association and a past executive of the International Sociological Association, he has penned a number of innovative essays on the tasks and role of sociology in South Africa and the South.
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The observatory was established by an endowment of £3,000 in the will of Francis Andrews, who was Provost of Trinity College Dublin at his death on 18 June 1774. The site was established on the south slope of a low hill in the townland of Dunsink, 84m above sea level.Ordnance Survey Map . Select Wind Report for elevation. Retrieved: 2011-02-22. The South Telescope or 12 inch Grubb, is a refracting (uses lens) telescope built by Thomas Grubb of Dublin, completed in 1868.
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Ngaujah is of Sierra Leonean ancestry. During the Christmas of 1999 he began the writing process that led to the short-story collection Refracting (Dasarts 2004), which inspired the piece Conversations with Ice Amsterdam- BitterZoet (Dasarts 2006). Over Het Ij Festival, Amsterdam, 2007 (Made n Da Shade/Cosmic Theater). Sahr has appeared at speaking engagements, at art conferences in Northern Europe (2007–08) about the construction and development of Conversations With Ice, with invitations pending to present this work in Sweden and Tokyo.
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From 1964, he decided to devote himself entirely to his career in visual art, his floral interest also finding expression in colour-refracting perspex sculpture and large abstract works in glass and steel using perspex. In painting he forged his own interpretation of international minimalism, creating works in watercolour on velum, of flowers, leaves and vegetables. His work is in the British Museum, V&A;, Tate Gallery, Scottish National Gallery of Modern Art, Hunt Institute, Pittsburgh and MOMA, New York, among other collections.
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The earliest stereoscopes, "both with reflecting mirrors and with refracting prisms", were invented by Sir Charles Wheatstone and constructed for him by optician R. Murray in 1832. Herbert Mayo shortly described Wheatstone's discovery in his book Outlines of Human Physiology (1833) and claimed that Wheatstone was about to publish an essay about it. It was only one of many projects of Wheatstone's and he first presented his findings on 21 June 1838 to the Royal College of London.Contributions to the Physiology of Vision.
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Whewell, 1857, p. 329. Printed label seen through a doubly-refracting calcite crystal and a modern polarizing filter (rotated to show the different polarizations of the two images) But Malus, in the midst of his experiments on double refraction, noticed something else: when a ray of light is reflected off a non-metallic surface at the appropriate angle, it behaves like one of the two rays emerging from a calcite crystal.Darrigol, 2012, pp. 191–2; Silliman, 1967, pp. 125–7.
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A method of astigmatism analysis by Alpins may be used to determine both how much surgical change of the cornea is needed and after surgery to determine how close treatment was to the goal. Another rarely used refraction technique involves the use of a stenopaeic slit (a thin slit aperture) where the refraction is determined in specific meridians – this technique is particularly useful in cases where the patient has a high degree of astigmatism or in refracting patients with irregular astigmatism.
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The shrimp has an eye of the refracting superposition type, in the rear behind this in each eye there is a single large facet that is three times in diameter the others in the eye and behind this is an enlarged crystalline cone. This projects an upright image on a specialised retina. The resulting eye is a mixture of a simple eye within a compound eye. Another version is a compound eye often referred to as "pseudofaceted", as seen in Scutigera.
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Computing the f-number of the human eye involves computing the physical aperture and focal length of the eye. The pupil can be as large as 6–7 mm wide open, which translates into the maximal physical aperture. The f-number of the human eye varies from about 8.3 in a very brightly lit place to about 2.1 in the dark. Sect. 5.7.1 Computing the focal length requires that the light-refracting properties of the liquids in the eye be taken into account.
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For wave propagation perpendicular towards a straight coast with depth contours parallel to the coastline, take b a constant, say 1 metre or yard. For refracting long waves in the ocean or near the coast, the width b can be interpreted as the distance between wave rays. The rays (and the changes in spacing between them) follow from the geometrical optics approximation to the linear wave propagation. In case of straight parallel depth contours this simplifies to the use of Snell's law.
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An old man finally destroyed the snake by holding up a mirror to her, which made her laugh so hard at her reflection that she died. Using images of the snake and the mirror, Allahyari takes us through a labyrinthine online narrative that mixes personal and imagined stories to address topics such as femininity, sexual abuse, morality, and hysteria. The snake emerges as a complex figure, reflecting multifaceted and sometimes distorted views of the female, and refracting images of otherness and monstrosity.
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New Haven:Yale University Press. pg 39 Ibn Sahl (c. 940-1000), a mathematician and physicist connected with the court of Baghdad, wrote a treatise On Burning Mirrors and Lenses in 984 in which he set out his understanding of how curved mirrors and lenses bend and focus light. Ibn Sahl is credited with discovering the law of refraction, now usually called Snell's law.K. B. Wolf, "Geometry and dynamics in refracting systems", European Journal of Physics 16, p. 14-20, 1995.
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The front lens is made of extremely high refracting glass in order to allow a small construction.M.ZUIKO DIGITAL ED 8 mm F1.8 Fisheye Pro - The world's first f1.8 high-performance fisheye lens , olympus-global.com, 12 May 2015, retrieved 12 November 2016 The ED 8 mm f/1.8 Fisheye Pro has an excellent image quality with low aberration.Andrew Alexander: Olympus 8 mm f/1.8 Pro M.Zuiko Digital ED FisheyeTweet, 29 May 2015, retrieved 12 November 2016 At fast aperture sizes (up to f = 2.8) there is visible vignetting.
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Mercury has dark zones which contrast with a brighter bottom; this was observed first by Giovanni Schiaparelli in 1889. By using the refracting telescope of the Pic du Midi Observatory, Dollfus was able in 1959 to clearly resolve surface features as small as 300 km. Dollfus also studied the possible presence of an atmosphere around the Moon. The rate of dissipation into space of any gases on the Moon (except for certain rare heavy elements) is so high that no substantial atmosphere is possible.
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A detector placed on the back side of the refracting prism would show a light and a dark region. Over a century after Abbe's work, the usefulness and precision of refractometers has improved, although their principle of operation has changed very little. They are also possibly the easiest device to use for measuring the refractive index of solid samples, such as glass, plastics, and polymer films. Some modern Abbe refractometers use a digital display for measurement, eliminating the need for discerning between small graduations.
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The observatory operates several telescopes at three locations in the Flagstaff area. The main facility, located on Mars Hill just west of downtown Flagstaff, houses the original Clark Refracting Telescope, which is now used for public education, with 85,000 annual visitors. The telescope, built in 1896 for $20,000, was assembled in Boston by Alvan Clark & Sons and then shipped by train to Flagstaff. Also located on the Mars Hill campus is the Pluto Discovery Telescope, used by Clyde Tombaugh in 1930 to discover the dwarf planet Pluto.
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Originally, the light comprised reflectors but changed to a dioptric (refracting) mechanism in 1838; the appearance of the original lantern is not known. The present lantern of 1856 is a 4.27 m (14 ft) wide chamfered octagon and the light remained fixed, instead of revolving. The present revolving apparatus was installed in 1873 and gives a group of five flashes, originally driven by a vapourising oil-lamp, but replaced by electric in 1973. The lighthouse is unusual in lacking any sort of harbour or quay facilities.
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His son followed in his footsteps and was a pivotal player in the popularisation of Copernicus's book De revolutionibus orbium coelestium. Notes written by Thomas Digges in the publication of the book Pantometria in 1570 contain descriptions of how Leonard Digges made use of a "proportional Glass" to view distant objects and people. Some, such as astronomer and historian Colin Ronan, claim this describes a reflecting or refracting telescope built between 1540 and 1559, but its vague description and claimed performance makes it dubious.
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In Galileo's 1604 observation of Kepler's Supernova and conclusion that it was a group of distant stars, Galileo disproved the Aristotelian notion of the immutability of the heavens. Using his refracting telescope, Galileo observed in late 1609 that the surface of the Moon is not smooth. Early the next year, he observed the four largest moons of Jupiter. Later in 1610, he observed the phases of Venus—a proof of heliocentrism—as well as Saturn, though he thought the planet's rings were two other planets.
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A small telescope is generally considered by professional astronomers to be any reflecting telescope with a primary mirror that is less than in diameter. By amateur standards, a small telescope can have a primary mirror/aperture less than in diameter. Little if any professional-level research is performed with refracting telescopes in the modern era of astronomy. Small telescopes dominate astronomical research in the fields of asteroid/comet discovery/observation, variable star photometry, supernova/nova discovery, and colorimetry/polarimetry of the Solar System's planets.
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Authors: D. Magrin, Ma. Munari, I. Pagano, D. Piazza, R. Ragazzoni, et al., in Space Telescopes and Instrumentation 2010: Optical, Infrared, and Millimeter Wave, Edited by Oschmann, Jacobus M., Jr.; Clampin, Mark C.; MacEwen, Howard A. Proceedings of the SPIE, Volume 7731, pp. 773124-8 (2010) The cameras are refracting telescopes using six lenses; each camera has an 1,100 deg2 field and a 120 mm lens diameter. Each camera is equipped with its own CCD staring array, consisting of four CCDs of 4510 x 4510 pixels.
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Relay lenses are found in refracting telescopes, endoscopes and periscopes for the purpose of extending the length of the system, and before eyepieces for the purpose of inverting an image. They may be made of one or more conventional lenses or achromatic doublets, or a long cylindrical gradient-index of refraction lens (a GRIN lens). Relay lenses operate by producing intermediate planes of focus. For example, an objective lens such as a SLR lens produces an image plane where the image sensor would usually go.
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The double refracting telescope at Le Houga was used extensively for studies of the planets and the teaching of young astronomers. In 1959 his observatory was part of an observational campaign regarding an occultation of Regulus by Venus. The team of Harvard observers at Le Houga was led by Gérard de Vaucouleurs, who had previously collaborated with Mr. Péridier on studies at the observatory. The success of the 1959 work started a five-year collaboration with NASA on photometry of the Moon and planets using a reflector.
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The first significant Canadian astronomical facility, the Dominion Observatory, was built in Ottawa in 1905 by the federal government. It featured a refracting telescope and a reflecting solar telescope. This was followed in 1918 by the new Dominion Astrophysical Observatory near Victoria, British Columbia. The 1.88 m (72 inch) reflecting telescope there had been proposed and designed by John Plaskett in 1910 with the backing of the International Union for Cooperation in Solar Research and when it began operation was briefly the largest telescope in the world.
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Due to its unique spot in the spectrum, 10 meters can occasionally be challenging to work. At peak times of the solar cycle when many sunspots appear on the Sun's surface, 10 meters can be alive with extremely long-distance signals, refracting from the F2 layer in the ionosphere. Generally speaking, the most effective and efficient propagation of 10-meter radio waves takes place during local daylight hours. During periods of increased sunspot activity, band openings may begin well before sunrise and continue into the night.
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In 1999, the brand "Sky-Watcher" was established to sell Synta Taiwan's optics with head offices in Richmond, British Columbia, Canada. From 2000, the first dobsonians were produced, then in 2001 the first Maksutov-Cassegrains, and in 2004 their first Apochromat ED-APO refracting telescopes. Since 2008, there has been cooperation with Schott AG, a German manufacturer of high-quality industrial glass. Sky-Watcher's product line-up contains telescopes from 2.4" (60 mm) up to 16" (406 mm) aperture with manual, motor-driven or GoTo mounts.
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Returning to London, in 1850 Gravatt was selected by the Reverend John Craig to design and construct the Craig telescope. Living in an apartment at 34 Parliament Street, his neighbours included the portrait photographer Richard Beard, who in 1852 came to take pictures of the instrument for the Illustrated London News. Designed as a great refractor, it was a refracting telescope with an achromatic doublet, giving an aperture of . The doublet was made with flint glass by Chance Brothers, and plate glass by Thames Plate Glass Company.
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The first phoropters. Top, the 1917 Woolf Ski-Optometer of New York City, with cylinder.; bottom, the 1917 DeZeng Phoro-Optometer model 570, Camden, NJ. The mounting arms on both devices attached at the bottom.The history of the phoropter, as a binocular refracting device which can also measure phorias, ductions, and other traits of binocularity, as distinct from the monocular optometer, which cannot, starts in the mid-1910s, with the introduction of the Ski-optometer by Nathan Shigon, and the Phoro-optometer by Henry DeZeng.
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Six years later, he became a US Marshal for the northern district of Illinois. In 1863, Hoyne traveled to New York and then to Boston to acquire a lens for a telescope for the University of Chicago. In Boston, he met with Alvan Clark and purchased an 18½-inch lens and mounting for the Dearborn Observatory, at the time, the largest refracting telescope ever built. By 1866, he became one of the founding members of the Chicago Astronomical Society and served as the organization's secretary.
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An engraving of Huygens's 210-foot aerial telescope showing the eyepiece and objective mounts and connecting string. An aerial telescope is a type of very long focal length refracting telescope, built in the second half of the 17th century, that did not use a tube. Instead, the objective was mounted on a pole, tree, tower, building or other structure on a swivel ball-joint. The observer stood on the ground and held the eyepiece, which was connected to the objective by a string or connecting rod.
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Wempe Glashütte Observatory, 2015 Glashütte Observatory is an observatory located in Glashütte, Saxony, Germany. Hugo Müller led the way and supplied a plot of land in Dittersdorfer Weg for the construction of an observatory, which began construction when the foundation stone was set on 27 August 1906. When the observatory opened four years later in 1910, on 26 June, it cemented Glashütte as the hub of Germany's watchmaking industry. It was furnished with a refracting telescope to precisely measure the Earth’s place in the Milky Way galaxy.
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The 86-foot (26 m) tall observatory (7 stories) is octagonal (to lessen wind pressure on each side) and lighthouse-shaped, with a fieldstone base of heavy loose rocks, and stands 222 feet (68 m) above sea level. There is no basement but the rock ballast in the bottom floor and octagonal design have kept the structure steady during storms. The observatory's 'lantern' (cupola) included a P & J Dollond Achromatic Refracting Telescope, which could identify ships 30 miles (48 km) to sea. That telescope disappeared from the observatory in 1939.
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His sends Foster on a date with Sarah, whilst he and Colonel Virginia Lake break-in and search her apartment. There they discover a refracting telescope with a transmitter powerful enough to reach the aliens - she has been passing information to them. Straker learns that the ship was going to dump nerve gas into the sea, but the aliens see an opportunity to release it into the atmosphere to kill everyone. Three UFOs are then detected heading for the ship, proving the aliens have managed to circumvented SHADO's detection systems.
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The image is formed from the whole array of sensors and is therefore tolerant to faults in individual sensors; on the other hand it accepts more background radiation than a focusing-optics imager (e.g., a refracting or reflecting telescope), and therefore is normally not favored at wavelengths where these techniques can be applied. The coded aperture imaging technique is one of the earliest forms of computational photography and has a strong affinity to astronomical interferometry. Aperture-coding was first introduced by Ables and Dicke and later popularized by other publications.
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Two of the four Unit Telescopes that make up the ESO's VLT, on a remote mountaintop, 2600 metres above sea level in the Chilean Atacama Desert. Optical telescopes have been used in astronomical research since the time of their invention in the early 17th century. Many types have been constructed over the years depending on the optical technology, such as refracting and reflecting, the nature of the light or object being imaged, and even where they are placed, such as space telescopes. Some are classified by the task they perform such as Solar telescopes.
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Refractors were the earliest type of optical telescope. The first record of a refracting telescope appeared in the Netherlands about 1608, when a spectacle maker from Middelburg named Hans Lippershey unsuccessfully tried to patent one.Albert Van Helden, Sven Dupré, Rob van Gent, The Origins of the Telescope, Amsterdam University Press, 2010, pages 3-4, 15 News of the patent spread fast and Galileo Galilei, happening to be in Venice in the month of May 1609, heard of the invention, constructed a version of his own, and applied it to making astronomical discoveries.
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Isotropic materials have symmetry in all directions and the refractive index is the same for any polarization direction. An anisotropic material is called "birefringent" because it will generally refract a single incoming ray in two directions, which we now understand correspond to the two different polarizations. This is true of either a uniaxial or biaxial material. In a uniaxial material, one ray behaves according to the normal law of refraction (corresponding to the ordinary refractive index), so an incoming ray at normal incidence remains normal to the refracting surface.
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Newton first demonstrated the presence of chromatic aberration in the human eye in 1670. He observed that isolated incident light rays directed at an opaque card held close to the eye strike the refracting surfaces of the eye obliquely and are therefore strongly refracted. Because the indices of refraction (see: Refractive Index) vary inversely with wavelength, blue rays (short wavelength) will be refracted more than red rays (long wavelength). This phenomenon is called chromatic dispersion and has important implications for the optical performance of the eye, including the stereoptic effect.
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The album's artwork depicts the light refracting from a triangular prism. The album was originally released in a gatefold LP sleeve designed by Hipgnosis and George Hardie. Hipgnosis had designed several of the band's previous albums, with controversial results; EMI had reacted with confusion when faced with the cover designs for Atom Heart Mother and Obscured by Clouds, as they had expected to see traditional designs which included lettering and words. Designers Storm Thorgerson and Aubrey Powell were able to ignore such criticism as they were employed by the band.
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The story is told by an Austin, Texas, therapist named Victoria Vick and centers around one of her clients, Y___, a man whose name the reader never learns. Y___ professes to be a scientist working on an aborted secret government project he calls "cloaking technology." With a combination of futuristic fabric and light-refracting cream, Y___ says he's able to make himself invisible. With his cloaking technology, Y___ claims to observe many people who think they are alone or otherwise believe they are not being watched, which he insists is essential to completing his research.
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The Anna L. Nickel telescope is a 1-meter reflecting telescope located at Lick Observatory in the U.S. state of California. The smaller dome on the main building at Lick had originally held the secondhand 12-inch Clark refracting telescope, the first telescope to be used at Lick. In 1979 it was replaced with the Anna L. Nickel telescope, a 1-meter reflecting telescope. The telescope is named for Anna L. Nickel, a San Francisco native who donated $50,000, a large portion of her estate, to the Observatory.
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The leaf includes a security feature that, when viewed close to the eye with a single- point light source behind, produces a circular image displaying the note's denomination. The window is fringed by maple leaves; at its top is a smaller version of the portrait, and at its bottom a light-refracting metallic likeness of an architectural feature from the parliament buildings. The portraits on the face are more centred on the note. The backs of the notes introduce new cultural and thematic imagery, but the literary quotation is not continued.
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The Cassini Division is a region in width between Saturn's A ring and B Ring. It was discovered in 1675 by Giovanni Cassini at the Paris Observatory using a refracting telescope that had a 2.5-inch objective lens with a 20-foot-long focal length and a 90x magnification.Archie Frederick Collins, The greatest eye in the world: astronomical telescopes and their stories, page 8 From Earth it appears as a thin black gap in the rings. However, Voyager discovered that the gap is itself populated by ring material bearing much similarity to the C Ring.
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Negative lens The simple negative lens placed before the focus of the objective has the advantage of presenting an erect image but with limited field of view better suited to low magnification. It is suspected this type of lens was used in some of the first refracting telescopes that appeared in the Netherlands in about 1608. It was also used in Galileo Galilei's 1609 telescope design which gave this type of eyepiece arrangement the name "Galilean". This type of eyepiece is still used in very cheap telescopes, binoculars and in opera glasses.
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As with all astronomers of the Struve family, Herman was mostly working on establishing position and movements of single and double stars and satellites of the planets of the Solar System. In 1885, a 30-inch refracting telescope was installed at Pulkovo, at the time the largest in the world (see great refractor). Struve was the first user of that telescope, which he used mostly for determining positions of a large number of double stars. His other major topic was Saturn, but he also studied Mars, Neptune and the fifth moon of Jupiter.
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In 1911, Lincoln became chairman of the board, a position he held until 1922. A serious amateur astronomer, Lincoln constructed an observatory at his home in Manchester, Vermont, and equipped it with a refracting telescope made in 1909 by Warner & Swasey with a six-inch objective lens by John A. Brashear Co., Ltd. Lincoln's telescope and observatory still exist; it has been restored and is used by a local astronomy club.Revised List of Telescopes by Warner & Swasey Company as augmented by E. N. Jennison from Records in Engineering Department, Warner & Swasey Corp.
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The Natal Observatory was initially equipped with a 200 mm Grubb equatorial refracting telescope donated by the Natal lawyer and politician Harry Escombe, a 75 mm Troughton & Simms transit instrument, a clock by Dent keeping sidereal time, and some precision clocks and other minor instruments.Neison, E. Report of the superintendent, Natal Observatory, for 1883-4, p. FF159 A mean time clock by Victor Kullberg was added in 1892Neison, E. Report of the superintendent, Natal Observatory, for 1892-3, p. F1 and a 75 mm portable equatorial refractor in 1896.
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The LHO's primary instrument was a refracting telescope for its entire span of operations. The lenses for the telescope were initially ordered in 1911, but due to the First World War, the two lens blanks were not delivered by Carl Zeiss Jena until 1923. They were then figured by James B. McDowell and Frederick Hageman of John A. Brashear, Co., a process which took over a year. The finished lenses were sent to Ann Arbor, where they were integrated into the great refractor built by the Detroit Observatory's machine shop.
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Contained within it is one of the most important collections of nineteenth-century scientific instruments, featuring a refracting telescope and a meridian circle manufactured by Repsold.American Astronomical Society, National Polytechnic School Establishes Division of Solar Physics Phenomena The 24 cm Merz Equatorial Telescope is the most important instrument of the Observatory. It was manufactured in 1875 in Munich, Germany and is mounted on an equatorial mount. Ecuador is located in a strategic geographical position where solar-physics studies can be performed year-round, providing data for the scientific community working to understand Sun-Earth interactions.
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Paracatenula can reach a length of up to 15 mm and a width of 0.4 mm. Several larger species of Paracatenula, such as P. galateia are flattened like a leaf, while all smaller species are round. All Paracatenula species examined so far were found to harbor bacterial symbionts in specialized symbiont-housing cells that form the nutritive organ - the trophosome. The frontal part of the worms - the rostrum - is transparent and bacteria-free, and houses the brain, while the trophosome region appears white due to light refracting inclusions in the bacterial symbionts.
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A footbridge crosses the railway approximately halfway along the length of the open part of the common. To the east of the railway line there is a large area which is mainly used for competitive sports (mostly football, touch rugby and rounders). Facilities include an educational centre in an area dedicated to wildlife known locally as 'The Scope' (named after the Craig telescope, which was once the largest refracting telescope in the world). There are also tennis courts, a bowling green and a cafe bar in the grounds, named 'The Skylark'.
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The opening ceremony of the building took place on July 29, 1938. Its official name was the "Observatory of the State Meteorological Institute", but soon it took on the nickname "Biały Słoń", due to the color of its walls. The observatory was lavishly equipped, with a custom-made astrograph and refracting telescope made by the renowned British company Grubb Parsons of Newcastle upon Tyne. It had its own power plant with two Diesel motor-generators and central heating fueled by oil, which was transported in iron barrels from the "Polmin" company in Borysław (today Boryslav).
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Seagrave Memorial Observatory is an astronomical observatory located in North Scituate, Rhode Island. It is named after astronomer Frank Evens Seagrave and is wholly owned and operated by Skyscrapers, Inc. The main instrument is an 8¼-inch Alvan Clark refracting telescope which was given to Frank Evens Seagrave for his 16th birthday in 1876, however the telescope took two years to build, so he did not receive it until 1878. The telescope and Seagrave Observatory (as the private observatory was then known) were originally at 119 Benefit Street in Providence.
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Modern microscopes, known as compound microscopes have many lenses in them (typically four) to optimize the functionality and enhance image stability. A slightly different variety of microscope, the comparison microscope, looks at side-by-side images to produce a stereoscopic binocular view that appears three dimensional when used by humans. The first telescopes, called refracting telescopes, were also developed with a single objective and eyepiece lens. In contrast to the microscope, the objective lens of the telescope was designed with a large focal length to avoid optical aberrations.
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It represented a shift in the thinking about observatories, from their being mere housing for telescopes and observers, to the early-20th-century concept of observation equipment integrated with laboratory space for physics and chemistry analysis. The observatory's main dome houses a 40-inch (102-cm) diameter doublet lens refracting telescope, the largest refractor ever successfully used for astronomy. Two smaller domes house 40-inch (102-cm) and 24-inch (61-cm) reflecting telescopes. There are several smaller telescopes - some permanently mounted - that are primarily used for educational purposes.
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Light path in a Newtonian telescope. A replica of Newton's second reflecting telescope which was presented to the Royal Society in 1672. In 1666 Isaac Newton, based on his theories of refraction and color, perceived that the faults of the refracting telescope were due more to a lens's varying refraction of light of different colors than to a lens's imperfect shape. He concluded that light could not be refracted through a lens without causing chromatic aberrations, although he incorrectly concluded from some rough experimentsIsaac Newton, Optics, bk. i. pt. ii. prop.
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The Schmidt–Cassegrain design is very popular with consumer telescope manufacturers because it combines easy-to-manufacture spherical optical surfaces to create an instrument with the long focal length of a refracting telescope with the lower cost per aperture of a reflecting telescope. The compact design makes it very portable for its given aperture, which adds to its marketability. Their high f-ratio means they are not a wide- field telescope like their Schmidt camera predecessor, but they are good for more narrow-field deep sky and planetary viewing.
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The color of the laser light itself is deep violet; but its wavelength is short enough to cause fluorescence in the glass, which re-radiates greenish light in all directions, rendering the zigzag beam visible. Refraction is generally accompanied by partial reflection. When waves are refracted from a medium of lower propagation speed to a medium of higher propagation speed (e.g., from water to air), the angle of refraction (between the refracted ray and the line perpendicular to the refracting surface) is greater than the angle of incidence (between the incident ray and the perpendicular).
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The ice crystals responsible for halos are typically suspended in cirrus or cirrostratus clouds in the upper troposphere (), but in cold weather they can also float near the ground, in which case they are referred to as diamond dust. The particular shape and orientation of the crystals are responsible for the type of halo observed. Light is reflected and refracted by the ice crystals and may split into colors because of dispersion. The crystals behave like prisms and mirrors, refracting and reflecting light between their faces, sending shafts of light in particular directions.
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Gravatt designed the mounting himself, built on Wandsworth Common, featuring a tall brick tower with a long telescope tube, built by Messrs Rennie. "The geography of the heavens: and class-book of astronomy: accompanied by a ..." By Elijah Hinsdale Burritt, Henry Whitall, Page 324. Internet Archive 2010 The eventual Craig telescope was the largest refracting telescope (a telescope with a lens) in the world from 1852.New Scientist: Dec 2, 1982 "The Monster Telescope at Wandworth" However, it had a problem with its lens figuring starting from its first light in the summer of 1852.
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Further information is obtained by inserting the lower polarizer and rotating the section. The light vibrates in only one plane, and in passing through doubly refracting crystals in the slide, is, speaking generally, broken up into rays, which vibrate at right angles to one another. In many colored minerals such as biotite, hornblende, tourmaline, chlorite, these two rays have different colors, and when a section containing any of these minerals is rotated the change of color is often clearly noticeable. This property, known as "pleochroism" is of great value in the determination of mineral composition.
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Two of these Charles Frederick (1836–98) and Thomas (1839–1919) subsequently joined him in the business he founded in 1836 at number 50 (now renumbered to 18) Stonegate, close to York Minster with the assistance of a loan of £100 from his wife's uncle. Cooke studied optics and became interested in making telescopes, the first of which was a refracting telescope with the base of a tumbler shaped to form its lens. This led to his friends including John Phillips encouraging him to make telescopes and other optical devices commercially.
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He exhibited at the York Exhibition in 1866 demonstrating his three-wheeled, steam-powered car which he claimed could carry 15 people at 15 mph for a distance of 40 miles. One of his finest achievements was the construction of the 25-inch 'Newall' refractor for Robert Stirling Newall; sadly, Thomas died before seeing it completed. For some years the Newall was the largest refracting telescope in the world. On Newall's death it was donated to the Cambridge Observatory and finally moved in 1959 to Mount Penteli observatory in Penteli, Greece.
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Diagram of a Gregorian reflecting telescope. In his 1663 Optica Promota, James Gregory described his reflecting telescope which has come to be known by his name, the Gregorian telescope. Gregory pointed out that a reflecting telescope with a parabolic mirror would correct spherical aberration as well as the chromatic aberration seen in refracting telescopes. In his design he also placed a concave secondary mirror with an elliptical surface past the focal point of the parabolic primary mirror, reflecting the image back through a hole in the primary mirror where it could be conveniently viewed.
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Mischtechnik can be a method of painting with egg tempera, used in combination with oil based paints and resins to render a luminous, resonant realism. The egg yolk of the egg tempera is a naturally occurring emulsion of water and oil. As such, the old masters found ways of extending the natural advantages of its emulsion to create lean, siccative, smoothly transitional, semi-transparent layers of paint. The visual effects created by working in the mixed technique essentially rely upon the phenomenon of light refracting through many subsequent layers of paint.
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The history of the Dearborn Observatory coincides with the founding of the Chicago Astronomical Society in 1862. The society heard of the 1861 construction of a lens for a telescope, which made it, at the time, the largest refracting telescope in the world. The lens had been commissioned by Frederick Augustus Porter Barnard, the chancellor of the University of Mississippi (later president of Columbia University), who hoped to found an observatory with the new lens. He commissioned the renowned firm of Alvan Clark & Sons of Cambridge, Massachusetts, to construct the lens.
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Latias is highly intelligent and can understand human speech. She can telepathically communicate with others. If Latias senses hostility towards herself, she will ruffle the feathers all over her body and cry shrilly to intimidate her foe. However, she will usually disappear if she senses an enemy, as they are able to use a form of active camouflage by enfolding their bodies with their glass-like coat of down and refracting light in unique ways, allowing them to become invisible or even take on the appearance of a human or another Pokémon.
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"Sunquakes" caused by solar flares were first observed during this cycle. These are running acoustic waves, as opposed to the standing waves that constitute the material of helioseismology. The flare impulse launches these waves from the photosphere, and they arc deeply into the interior of the Sun before refracting back to the surface to appear as faint ripples, expanding radially away from the flare some tens of minutes later. The flare in which these waves were first observed, SOL1996-07-09, occurred more than three years after the last previous major event.
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To the north of Schröter, beginning with the satellite crater Schröter W, is a region of irregular terrain. This area includes an array of linear dark surface markings that appear to criss-cross. In the 19th century, Franz von Gruithuisen is noted for claiming that this area contained a lunar city (which he called Wallwerk), based on his observations using a small refracting telescope. This inference was greeted with considerable skepticism by astronomers at the time, and, indeed, subsequent observations with more powerful instruments demonstrated that this was merely a natural feature.
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Thus, he observed that colour is the result of objects interacting with already-coloured light rather than objects generating the colour themselves. This is known as Newton's theory of colour. Illustration of a dispersive prism separating white light into the colours of the spectrum, as discovered by Newton From this work, he concluded that the lens of any refracting telescope would suffer from the dispersion of light into colours (chromatic aberration). As a proof of the concept, he constructed a telescope using reflective mirrors instead of lenses as the objective to bypass that problem.
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Ortiz de Landázuri relocated to Rome in 1956 in order to work with Escrivá in the governance of Opus Dei. Not long after her arrival, she noted pain in her chest which turned out to be a serious heart condition, and she returned to Madrid for an operation. After partially recovering, she continued with her academic work, now in Spain. During this time, she began a research project on insulating refracting materials from rice husks; she won the prize Juan de la Cierva for this project and finally completed and defended her doctoral thesis on 8 July 1965.
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Eudicella gralli, sometimes called the flamboyant flower beetle or striped love beetle, is a brightly coloured member of the scarab beetle family, in the subfamily known as flower beetles. Their shells seem to have a prismatic quality, refracting the ambient light to give the green of their carapace a rainbow tint. This species of flower beetle lives in the rainforests of Africa, where it feeds on the nectar and pollen of flowers, but is popular in the exotic pet trade. The larvae of the flower beetle live in decaying wood, feeding on dead wood and leaf litter.
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Each Saturday exhausted his funds and on Monday he had to begin collecting again. But, nothing daunted or discouraged the invincible enthusiast, he stuck resolutely to his task until it was done, and in March 1845 he had the satisfaction of hoisting his telescope into place. At the time, it was the second-largest refracting telescope in the world. There was no salary attached to the office of astronomer in this new observatory and Mitchel supported himself by civil engineering on the route of the Ohio & Mississippi Railroad (Ohio and Mississippi Railway) and by lecturing anywhere and everywhere.
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A photometer was deployed on the 254 mm (10") refractor roughly between the years 1957 and 1960. The first research from this instrument was the study of the brightness of Comet Arend-Roland by William and Amelia Wehlau, using data from 1957 and 1958. This combination of instruments was also used in the published search for variability in the stars Gamma Equulei and HD 149728, using 1958 and 1959 data from the refracting telescope. In 1960 a 300 mm (12") Cassegrain reflector (purchased in 1958) came online with a locally built photometer, and this combination of equipment supplanted the photometer on the refractor.
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It is probably best known internationally for being home to the University of Chicago's Yerkes Observatory, which houses the world's largest refracting (lens) telescope, the great 40-inch. Construction of the Observatory began in 1895 and the 40-inch saw first light in May 1897. The Observatory's first Director was George Ellery Hale, who went on to establish Mount Wilson Observatory in Southern California. Officials and students of Chicago-based George Williams College frequently met just west of the town of Williams Bay and later established a camp in the village on the shores of Geneva Lake.
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The Shuckburgh telescope or Shuckburgh equatorial refracting telescope was a diameter aperture telescope on an equatorial mount completed in 1791 for Sir George Shuckburgh (1751–1804) in Warwickshire, England, and built by British instrument maker Jesse Ramsden (1735–1800).... The Shuckburgh telescope is described on p. 99. It was transferred to the Royal Observatory, Greenwich in 1811 and the London Science Museum in 1929. Even though it has sometimes not been regarded as particularly successful, its design was influential. It was one of the larger achromatic doublet telescopes at the time, and one of the largest to have an equatorial mount.
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He specialized in celestial mechanics, in particular the motions of the satellites of Saturn. In 1903, the observatory took over a facility on the Pic du Midi in the Pyrenees that had been founded by amateurs in the 1850s with the goal of putting a telescope there. However, the height of 2865 metres (9400 feet) posed formidable logistical challenges and the ambition had remained unrealised though a meteorological observatory had operated from 1873 to 1880. Baillaud organised a team of soldiers to erect a 0.5 metre (20 inch) reflecting telescope, and 0.25 metre refracting telescope on the summit.
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The topic of gravity was not dealt with in a single section, showing that his understanding of the matter was still far from well developed. In a section on perpetual motion machines (folio 121) he wrote > Whether ye rays of gravity may be stopped by reflecting or refracting ym, if > so a perpetual motion may be made one of these ways. Elsewhere, in his notes on Kepler's laws of planetary motion that he read about in the book Astronomiae carolina by Thomas Streete, he reached the conclusion that gravity must not merely act on the surfaces of bodies but on their interiors.
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The normal at B1 can also be calculated from the directions of the incoming and outgoing rays at this point and the refractive index of the lens. Now we can repeat the process taking a ray r2 coming from R1 and refracting it at B1. Choosing now the optical path length S11 between R1 and S1 we have one condition that allows us to calculate point T1 on the top surface of the lens. The normal at T1 can also be calculated from the directions of the incoming and outgoing rays at this point and the refractive index of the lens.
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A symbol-intensive brand is a brand adopted not only for its functional benefits, but above all, for the strong symbolism and significance that it is able to transmit, allowing a consumer to express his or her identity, to signal status or manifest a sense of belonging to a group. Businesses might be based on three different types of knowledge: analytical; synthetic or symbolic. Creative or cultural businesses, such as entertainment, publishing, design, or fashion, draw heavily on a symbolic knowledge base. They serve important symbolic functions such as capturing, refracting, and legitimating social knowledge and values.
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Solar filters block most of the sunlight to avoid any damage to the eyes. Proper filters are usually made from a durable glass or polymer film that transmits only 0.00001% of the light. For safety, solar filters must be securely fitted over the objective of a refracting telescope or aperture of a reflecting telescope so that the body does not heat up significantly. Small solar filters threaded behind eyepieces do not block the radiation entering the scope body, causing the telescope to heat up greatly, and it’s not unknown for them to shatter from thermal shock.
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The largest practical lens size in a refracting telescope is around 1 meter, although Alvan G. Clark, who had made the Yerkes 40-inch objective, said a 45-inch (114 cm) would be possible before he died. In addition to the lens, the rest of the telescope needed to be a practical and highly precise instrument, despite the size. For example, the Yerkes tube alone weighed 75 tons, and had to track stars just as accurately as a smaller instrument. Observer end of the Lick telescope The choice between large refractors or reflectors was driven by the technology of the time.
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Convex lens A simple convex lens placed after the focus of the objective lens presents the viewer with a magnified inverted image. This configuration may have been used in the first refracting telescopes from the Netherlands and was proposed as a way to have a much wider field of view and higher magnification in telescopes in Johannes Kepler's 1611 book Dioptrice. Since the lens is placed after the focal plane of the objective it also allowed for use of a micrometer at the focal plane (used for determining the angular size and/or distance between objects observed).
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Smith was often involved in the cutting edge of photographic techniques: in 1931 he started experimenting with high-speed flash photography of action subjects, and started doing color work in 1936 when few people considered it a serious artistic medium. His later images were nearly all abstract, often made directly (without a camera, i.e. like photograms), for instance images created by refracting light through splashes of water and cliché verre images with corn syrup on a glass plate. However, although acclaimed as a photographic teacher, Holmes' own photographs and other images did not achieve any real recognition from his peers.
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Like others before and since his time, Gruithuisen believed that the Earth's moon was habitable. He made multiple observations of the lunar surface that supported his beliefs, including his announcement of the discovery of a city in the rough terrain to the north of Schröter crater he named the Wallwerk. This region contains a series of somewhat linear ridges that have a fishbone-like pattern, and, with the small refracting telescope he was using, could be perceived as resembling buildings complete with streets. He published his observations in 1824, but they were greeted with much skepticism by other astronomers of the time.
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The lenses of the prism spectrometer are used for both collimation and re-imaging; however, the imaging spectrometer is limited in its performance by the image quality provided by the collimators and re- imagers. The resolution of the slit image at each wavelength limits spatial resolution; likewise, the resolution of optics across the slit image at each wavelength limits spectral resolution. Moreover, distortion of the slit image at each wavelength can complicate the interpretation of the spectral data. The refracting lenses used in the imaging spectrometer limit performance by the axial chromatic aberrations of the lens.
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In 2015, Williams designed the giant kinetic chandelier installed at Omnia nightclub at Caesars Palace in Las Vegas. He has exhibited his own kinetic light sculptures in several art galleries. The sculptures, entitled "Lumia Domestica", create kaleidoscopic projections in the tradition of Nicolas Schoffer and Thomas Wilfred by refracting light through household glassware. Other public works include the creation of lighting installations at London's Southbank Centre and within Canterbury Cathedral; "SkyChurch", a multimedia performance space at the Experience Music Project in Seattle, Washington, and a permanent exhibit at Cleveland's Rock and Roll Hall of Fame Museum.
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Variations on the optical schlieren method include the replacement of the knife-edge by a coloured target, resulting in rainbow schlieren which can assist in visualising the flow. Different edge configurations such as concentric rings can also give sensitivity to variable gradient directions, and programmable digital edge generation has been demonstrated as well using digital displays and modulators. The adaptive optics pyramid wavefront sensor is a modified form of schlieren (having two perpendicular knife edges formed by the vertices of a refracting square pyramid). Complete schlieren optical systems can be built from components, or bought as commercially available instruments.
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Patent US1651412 (pag.2) of The Porter Garden Telescope (refractor version) by Russell W. Porter He presented the application of patent on 25 January 1922 and was conceded the same on 25 September 1923 under number US1468973. However, the final model differed of the aforementioned patent in the zone of the base, since there were later modifications of design that were collected in a new patent for a refracting telescope version. Although it presented the application some months after the first, 7 September 1922, it was conceded years later, on 6 December 1927 under number US1651412 but it was never manufactured.
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Famous astronomers were not retained, such as Heinrich Christian Schumacher (Director 1813–1815), founder of the oldest existing journal of astronomy, Astronomische Nachrichten, and of the Altona Observatory. Friedrich Wilhelm Struve, founder and first director of Pulkovo Observatory at St. Petersburg, despite being interested was deterred by clumsy personnel policy. From 1816 until his death in 1846 Bernhard Nicolai was Court Astronomer, being mainly dedicated to the orbits of comets. In his time, amongst other things, a three-stage refracting telescope was purchased from Fraunhofer, which was later used by the German expeditions of 1874 and 1882 to observe the Transit of Venus.
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Schiaparelli is famous for making hand-drawn maps of Mars during its 1877 oppositions with Earth with an optical refracting telescope. He was also the first astronomer to determine the relationship between comet debris and yearly meteor showers. Other things named for Schiaparelli include the main-belt asteroid 4062 Schiaparelli, named on 15 September 1989 (), the lunar crater Schiaparelli, the Martian crater Schiaparelli, Schiaparelli Dorsum on Mercury, and the 2016 ExoMars EDM lander. The mission was named in November 2013; previously it was known as the Exomars Entry, descent and landing Demonstrator Module, or ExoMars EDM for short.
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The ideal composition was around 68.21% copper to 31.7 % tin; more copper made the metal more yellow, more tin made the metal more blue in color.Norman W. Henley et al: Speculum Metal Ratios with up to 45% tin were used for resistance to tarnishing. Although speculum metal mirror reflecting telescopes could be built very large, such as William Herschel's 126-cm (49.5-inch) "40-foot telescope" of 1789 and Lord Rosse 1845 183-cm (72-inch) mirror of his "Leviathan of Parsonstown", impracticalities in using the metal made most astronomers prefer their smaller refracting telescope counterparts.Edison Pettit: The Reflector.
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Since crafting large lenses is much more difficult than crafting large mirrors, most modern telescopes are reflecting telescopes, that is, telescopes that use a primary mirror rather than an objective lens. The same general optical considerations apply to reflecting telescopes that applied to refracting telescopes, namely, the larger the primary mirror, the more light collected, and the magnification is still equal to the focal length of the primary mirror divided by the focal length of the eyepiece. Professional telescopes generally do not have eyepieces and instead place an instrument (often a charge-coupled device) at the focal point instead.
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Steward Observatory owes its existence to the efforts of American astronomer and dendrochronologist Andrew Ellicott Douglass. In 1906, Douglass accepted a position as Assistant Professor of Physics and Geography at the University of Arizona in Tucson, Arizona. Almost immediately upon his arrival in Tucson, Douglass established astronomical research programs using an 8-inch refracting telescope on loan from the Harvard College Observatory and actively began to pursue funding to construct a large research-class telescope in Tucson. Over the next 10 years, all of Douglass’ efforts to secure funding from the University and the Arizona Territorial (and later State) Legislatures ended in failure.
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Selenite wedges, selenite plates, mica wedges and mica plates are also used for this purpose. A quartz wedge also may be calibrated by determining the amount of double refraction in all parts of its length. If now it be used to produce compensation or complete extinction in any doubly refracting mineral section, we can ascertain what is the strength of the double refraction of the section because it is obviously equal and opposite to that of a known part of the quartz wedge. A further refinement of microscopic methods consists of the use of strongly convergent polarized light (conoscopic methods).
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If the analyzer is inserted in such a position that it is crossed relatively to the polarizer, the field of view will be dark where there are no minerals or where the light passes through isotropic substances such as glass, liquids and cubic crystals. All other crystalline bodies, being doubly refracting, will appear bright in some position as the stage is rotated. The only exception to this rule is provided by sections which are perpendicular to the optic axes of birefringent crystals, which remain dark or nearly dark during a whole rotation, the investigation of which is frequently important.
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The most common type of telescope at that time was the refracting telescope, which involved the refraction of light through a tube using a convex glass lens. This design was subject to chromatic aberration, a distortion of an image due to the failure of light of different component wavelengths to converge. Optician John Dollond (1706–1761) tried to correct for this distortion by combining two separate lenses, but it was still difficult to achieve good resolution for far distant light sources. Reflector telescopes, invented by Isaac Newton in 1668, used a single concave mirror rather than a convex lens.
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Some insects have a so-called single lens compound eye, a transitional type which is something between a superposition type of the multi-lens compound eye and the single lens eye found in animals with simple eyes. Then there is the mysid shrimp, Dioptromysis paucispinosa. The shrimp has an eye of the refracting superposition type, in the rear behind this in each eye there is a single large facet that is three times in diameter the others in the eye and behind this is an enlarged crystalline cone. This projects an upright image on a specialized retina.
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Vergara was a professor of Astronomy of the . Vergara was the Director of the Observatory of Montevideo, a professor at the Surveying Institute of the , and a professor at the Batlle y Ordóñez Institute when it was the Women's Institute. Vergara encouraged her students to buy a 10 cm Unitron refracting telescope that was used to inaugurate the Observatory of the Women's Institute of Secondary Education, Batlle y Ordóñez Institute (IBO), of which she was one of the founders in January 1976. She was one of the founders of the National Committee of Astronomy of Uruguay.
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To some it may be more desirable to utilize a telescope in which case far more options for observing the Moon exist. Even a small, well- made telescope will show the observer much greater detail than is visible with the naked eye or small binoculars. As the aperture of the telescope mirror (in the case of a reflecting telescope) or lens (in the case of a refracting telescope) increases, smaller and smaller features will begin to appear. With large amateur telescopes, features as small as 0.6 miles (1 km) in diameter can be observed depending on atmospheric conditions.
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Guy Lowell died in 1927, and the trusteeship of Lowell Observatory passed to Roger Putnam. Percival Lowell had predicted the existence of a "Planet X"—a possible ninth planet—in 1905, but his subsequent death in 1916 and Constance Lowell's lawsuit had largely mothballed the search for the celestial body. Putnam, however, was determined to find "Planet X." Spending several months a year at the Lowell Observatory, Putnam resolved to build a new refracting telescope and astrograph at the Observatory to revive the search. The reluctant staff hesitated to spend the Observatory's limited funds on the new telescope until Putnam forced the issue.
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In it, a new, more powerful revolving optic was installed, designed by James Timmins Chance: a six-sided symmetrical optic of the first-order, with refracting prisms above and below the central lens elements. At the time its six lens panels (at 60° to the circle) were 'the widest in azimuth hitherto constructed, except some of those of Flamborough Head'; the increase in power, compared to the old 45° lenses, was of the order of 3 to 2. Apparatus of the same design were installed the following year in lighthouses at South Stack and Cape Bon.
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Conventional telescope designs require reflection or refraction in a manner that does not work well for X-rays. Visible light optical systems use either lenses or mirrors aligned for nearly normal incidence – that is, the light waves travel nearly perpendicular to the reflecting or refracting surface. Conventional mirror telescopes work poorly with X-rays, since X-rays that strike mirror surfaces nearly perpendicularly are either transmitted or absorbed – not reflected. Lenses for visible light are made of transparent materials with an index of refraction substantially different from 1, but all known X-ray-transparent materials have index of refraction essentially the same as 1, so X-ray lenses are not practical.
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In contrast, if multiple feeds are used with a parabolic reflector, all must be within a small angle of the optical axis to avoid suffering coma (a form of de-focussing). Apart from offset systems, dish antennas suffer from the feed and its supporting structure partially obscuring the main element (aperture blockage); in common with other refracting systems, the Luneburg lens antenna avoids this problem. A variation on the Luneburg lens antenna is the hemispherical Luneburg lens antenna or Luneburg reflector antenna. This uses just one hemisphere of a Luneburg lens, with the cut surface of the sphere resting on a reflecting metal ground plane.
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However, Wheatstone's invention was impractical until Sir David Brewster, a Scottish physicist and experimenter of optics, discovered that a 3D effect could be observed in repeated patterns with small difference in 1844. Brewster used what he discovered in building the stereo camera. The stereo camera combined the refracting stereoscope with two separate cameras which were placed slightly apart. The monocular pictures through the cameras gave the resulting image a 3D effect. In 1846, W Rollman invented 3D anaglyphs, which are two sets of superimposed identical line drawing(one in blue and the other in red), which when viewed through red and blue glasses, appeared to be three- dimensional.
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Stratospheric Observatory for Infrared Astronomy 24 inch convertible Newtonian/Cassegrain reflecting telescope on display at the Franklin Institute A reflecting telescope (also called a reflector) is a telescope that uses a single or a combination of curved mirrors that reflect light and form an image. The reflecting telescope was invented in the 17th century, by Isaac Newton, as an alternative to the refracting telescope which, at that time, was a design that suffered from severe chromatic aberration. Although reflecting telescopes produce other types of optical aberrations, it is a design that allows for very large diameter objectives. Almost all of the major telescopes used in astronomy research are reflectors.
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A replica of Newton's second reflecting telescope that he presented to the Royal Society in 1672 The great telescope of Birr, the Leviathan of Parsonstown. Modern day remnants of the mirror and support structure. The idea that curved mirrors behave like lenses dates back at least to Alhazen's 11th century treatise on optics, works that had been widely disseminated in Latin translations in early modern Europe. Soon after the invention of the refracting telescope, Galileo, Giovanni Francesco Sagredo, and others, spurred on by their knowledge of the principles of curved mirrors, discussed the idea of building a telescope using a mirror as the image forming objective.
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A.R. Gibbs of the Mount Lemmon Observatory in Arizona discovered the comet based on images acquired by the sky survey's 1.5-m reflecting telescope on 23 March 2012. However, Gibbs did not recognize its cometary appearance and was listed as an asteroid on the Minor Planet Center's Near Earth Object confirmation page. At the time, the apparent magnitude of the comet was estimated between +20.6 and +20.8. Shortly after initial discovery, amateur astronomer Peter Birtwhistle in Great Shefford observed the comet using a 40-cm refracting telescope and CCD images, estimating an apparent magnitude of +20.1 and a diameter stretching 5 arc seconds across.
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With the support of Governor of the VOC- rule Dutch Cape Colony Ryk Tulbagh, French astronomer Nicolas-Louis de Lacaille studied the stars of the southern hemisphere from 1750 until 1754 from Cape of Good Hope, when he was said to have observed more than 10,000 stars using a refracting telescope. Seventeen southern constellations were newly created in 1763 by Lacaille appearing in his star catalogue, published in 1756. Black swans on the shore of the Swan River (Western Australia), with the Perth skyline in the background. The thousand-year-old conclusion "all swans are white" was disproved by the VOC navigator Willem de Vlamingh's 1697 discovery.
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A copyscope is type of refracting telescope that can be made by hand rather than bought in which the objective lens comes from an old photocopy machine, hence the origin of the name. The lenses usually come from defective or old photocopiers, allowing for the objective to be obtained for free or at a low cost. They are usually modest diameter lenses, ranging from 50mm to 60mm, of short focal length, good for use in a portable, wide-field telescope, but unsuitable for higher magnifications. Given the use of good components, however, a copyscope can become a rich-field instrument capable of reaching many extended objects and even star fields.
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A replica of the earliest surviving telescope attributed to Galileo Galilei, on display at the Griffith Observatory In 1609, Galileo was, along with Englishman Thomas Harriot and others, among the first to use a refracting telescope as an instrument to observe stars, planets or moons. The name "telescope" was coined for Galileo's instrument by a Greek mathematician, Giovanni Demisiani, at a banquet held in 1611 by Prince Federico Cesi to make Galileo a member of his Accademia dei Lincei.Rosen, Edward, The Naming of the Telescope (1947) In 1610, he used a telescope at close range to magnify the parts of insects. By 1624, Galileo had used a compound microscope.
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Aldershot observatory is a circular red-brick building with a domed roof standing on Queens Avenue in Aldershot Military Town near Aldershot, England, home to the British Army since circa 1854. Inside is an refracting telescope on a German-type equatorial mount with a clockwork drive which will run for about 2 hours without rewinding, this has a facility to vary the drive rate. The telescope and observatory building were a gift from aviation pioneer Patrick Young Alexander to the British Army, a fact which is recorded by a plaque near the observatory door. It reads: ‘Presented to the Aldershot Army Corps by Patrick Y Alexander Esq 1906’.
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Ray dealt with radioactive rare-earth elements, which today are essential for the production of smartphones and LEDs. These were extensively studied in the late 1880s at the Barringer Hill mine in Llano, Texas, which now lies beneath Lake Buchanan. During a 2013 research trip Kriemann explored the lake, on whose bottom the ores now rest, to assess its photographic suitability as a light-refracting optical lens for the mine below. Whereas the Texas mine was approached from the perspective of a material archaeology of ecological, economic, political, and chemical processes, Ashes and Broken Brickwork of a Logical Theory (2009–10) dealt with actual archaeology.
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Newton's idea for a reflecting telescope was not new. Galileo Galilei and Giovanni Francesco Sagredo had discussed using a mirror as the image forming objective soon after the invention of the refracting telescope, and others, such as Niccolò Zucchi, claimed to have experimented with the idea as far back as 1616.The Galileo Project > Science > Zucchi, Niccolo Newton may even have read James Gregory's 1663 book Optica Promota which described reflecting telescope designs using parabolic mirrors (a telescope Gregory had been trying unsuccessfully to build). Newton built his reflecting telescope because he suspected it could prove his theory that white light is composed of a spectrum of colours.
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Hodgins In 1881 the observatory's director, Charles Carpmeal, suggested adding a high-quality telescope to the observatory. He felt that direct solar observations would lead to a better understanding of sunspot effects on weather (as late as 1910 the observatory's then-director, R. F. Stupart, noted that "sun spots have more to do with our weather conditions than have the rings around the moon."). Coincidentally, the Canadian government (having formed in 1867) was interested in taking part in the major international effort to accurately record the December 1882 Transit of Venus. Funds were provided for the purchase of a 6-inch (150 mm) refracting telescope from T. Cooke & Sons.
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Rigid gas-permeable (RGP) lens A rigid gas-permeable lens, also known as RGP lens or GP lens or colloquially, hard contact lens, is a rigid contact lens made of oxygen-permeable polymers. Initially developed in the late 1970s, and through the 1980s and 1990s, they were an improvement over prior 'hard' lenses that restricted oxygen transmission to the eye. Rigid lenses are able to replace the natural shape of the cornea with a new refracting surface. This means that a regular (spherical) rigid contact lens can provide good level of vision in people who have astigmatism or distorted corneal shapes as with keratoconus.
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After a 5-year hiatus from astronomy, Douglass left Flagstaff, Arizona in 1906 and accepted a position as Assistant Professor of Physics and Geography at the University of Arizona in Tucson, Arizona. Almost immediately upon his arrival in Tucson, Douglass re-established his astronomical research programs using an 8-inch refracting telescope on loan from the Harvard College Observatory and actively began to pursue funding to construct a large research-class telescope in Tucson. Over the next 10 years Douglass was unable to secure funding from the University and the Arizona Territorial (and later State) Legislatures. During this period Douglass served the University of Arizona as Head of the Dept.
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When plane-polarised light passes through some crystals, the velocity of left-polarised light is different from that of the right-polarised light thus the crystals are said to have two refractive indices i.e. double refracting Construction: It consists of a monochromatic source S which is placed at focal point of a convex lens L. Just after the convex lens there is a Nicol Prism P which acts as a polariser. H is a half shade device which divides the field of polarised light emerging out of the Nicol P into two halves generally of unequal brightness. T is a glass tube in which optically active solution is filled.
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Although Common's professional career was in the field of sanitary engineering, he is most noted for the work he did as an amateur in the field of astronomy. As a child Andrew showed interest in astronomy. At age 10 his mother borrowed a telescope for him to use from a local doctor, Dr. Bates of Morpeth. He returned to astronomy in his 30s when he took up experimenting with gelatin plate photography of the moon and planets with a 5.5 inch refracting telescope. Common's 18-inch reflector in his garden shed in the 1870s at his house in Ealing In 1876 Common became a Fellow of the Royal Astronomical Society.
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Under Howard Grubb the Grubb Telescope Company gained an even greater reputation for quality optical instruments. Grubb was also known for building accurate electrically driven clock drives for equatorial mounted telescopes. Some of the telescopes produced by Howard Grubb include the 27-inch refractor for the Vienna Observatory (1878), the 10-inch refractor at Armagh Observatory (1882), the 28-inch refractor at the Royal Observatory, Greenwich – the UK's largest refractor (1893), and the 10-inch refractor at Coats Observatory, Paisley (1898). In 1887 Grubb's firm built seven normal astrographs for the Carte du Ciel international photographic star catalogue project, 13-inch refracting telescopes all designed to produce uniform photographic plates.
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Figure 2 A point O (fig. 2) at a finite distance from the axis (or with an infinitely distant object, a point which subtends a finite angle at the system) is, in general, even then not sharply reproduced if the pencil of rays issuing from it and traversing the system is made infinitely narrow by reducing the aperture stop; such a pencil consists of the rays which can pass from the object point through the now infinitely small entrance pupil. It is seen (ignoring exceptional cases) that the pencil does not meet the refracting or reflecting surface at right angles; therefore it is astigmatic (Gr. a-, privative, stigmia, a point).
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The versatility of dielectric coatings leads to their use in many scientific optical instruments (such as lasers, optical microscopes, refracting telescopes, and interferometers) as well as consumer devices such as binoculars, spectacles, and photographic lenses. Dielectric layers are sometimes applied over top of metal films, either to provide a protective layer (as in silicon dioxide over aluminium), or to enhance the reflectivity of the metal film. Metal and dielectric combinations are also used to make advanced coatings that cannot be made any other way. One example is the so- called "perfect mirror", which exhibits high (but not perfect) reflection, with unusually low sensitivity to wavelength, angle, and polarization.
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In 1839, Bond was allowed to move his personal astronomical equipment to Harvard and serve as its (unpaid) "Astronomical Observer to the University." Later, in 1843, a sun-grazing comet aroused enough public interest in astronomy that Harvard was able to raise $25,730 towards the construction of a state-of-the-art observatory. Bond designed the building and the observing chair (both of which are still in working order today), and Harvard bought a fifteen-inch German- built refracting telescope, equal in size to the largest in the world at the time. The telescope was first put to use on June 24, 1847, when it was pointed at the moon.
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Like Gregory and Hall, he argued that since the various humours of the human eye were so combined as to produce a perfect image, it should be possible by suitable combinations of lenses of different refracting media to construct a perfect telescope objective. Adopting a hypothetical law of the dispersion of differently colored rays of light, he proved analytically the possibility of constructing an achromatic objective composed of lenses of glass and water. All of Euler's efforts to produce an actual objective of this construction were fruitless—a failure which he attributed solely to the difficulty of procuring lenses that worked precisely to the requisite curves.Mem. Acad. Berlin, 1753.
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View through a 4× rifle scope Leupold and Stevens Mark 6 scope with variable magnification X3-X18, mounted on an M24 SWS A telescopic sight, commonly called a scope, is an optical sighting device that is based on a refracting telescope. It is equipped with some form of graphic image pattern (a reticle) mounted in an optically appropriate position in its optical system to give an accurate aiming point. Telescopic sights are used with all types of systems that require accurate aiming but are most commonly found on firearms, particularly rifles. Other types of sights are iron sights, reflector (reflex) sights, and laser sights.
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Phoroptor is a registered trademark currently owned by Reichert Technologies, filed Apr 25, 1921 by DeZeng Standard of New Jersey, with the USPTO, serial number 71146698. The word was coined at that time for the newest version of their phoro-optometer. DeZeng was purchased in 1925 by American Optical of Massachusetts, which continued to market the product, but the term, often spelled phoropter, has become a genericised trademark for all brands of modern vision testers, especially since AO's main competitor, Bausch and Lomb, stopped making their Greens' Refractor in 1970s. Reichert bought AO's refracting equipment division in 1980s, and their current version is named "Ultramatic Rx Master Phoroptor".
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This telescope, which saw its first light in 1934, has a corrector plate diameter of 500 mm, and a primary mirror focal length of 1031 mm. The spherical primary mirror diameter is 600 mm, and it is on a German-type equatorial mount. It uses a 120-mm diameter doubly convex field flatten lens 3 mm in front of the focal plane, which gives it a 6.7 degree diameter field of view on 120x120 mm film plates giving a scale of 200 arc-seconds per millimeter. The guide telescopes are 180 mm diameter/2300 mm focal length and 80 mm diameter/1200 mm focal length refracting telescopes.
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Suppose a doubly refracting mineral section so placed that it is "extinguished"; if now is rotated through 45 degrees it will be brightly illuminated. If the quartz wedge be passed across it so that the long axis of the wedge is parallel to the axis of elasticity in the section the polarization colors will rise or fall. If they rise the axes of greater elasticity in the two minerals are parallel; if they sink the axis of greater elasticity in the one is parallel to that of lesser elasticity in the other. In the latter case by pushing the wedge sufficiently far complete darkness or compensation will result.
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Jones (1999), p. 597. The essay goes on to explore this complex triple-identity. Jones concludes: "Marshall's novel is a radical expression of how the black self, when it exists at the intersections of ethnicity, nationhood, and gender, has its wholeness challenged by alternative and frequently conflicting definitions. Just as the sea in Brown Girl contains contradictory multitudes—it is the sea of female creativity, diasporic consciousness, and African history, yet also the sea of colonial exploitation, industrial decay, and obliteration of the black past—Marshall’s novel as a whole proposes a sense of selfhood which, like a prism, contains many faces, each one refracting at an acute angle of difference".
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Sir Thomas Brisbane, before finally departing Sydney for the last time in December 1825, arranged to sell all of his instruments to the Government so the observatory could continue to function. Some of the equipment he gave to Dunlop, which he used at his home, especially the useful small equatorial mounted refracting telescope that Rümker, and later Dunlop, both used for doing the important double stars measures as their own personal projects. By May 1826, Rümker returned to the observatory, and seven months later he was appointed as the first New South Wales Government Astronomer, though this officially did not happen until a few years later, much to Rümker's disgust, due to delays from his employers in Britain.
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A Fata Morgana of a boat This optical phenomenon occurs because rays of light are strongly bent when they pass through air layers of different temperatures in a steep thermal inversion where an atmospheric duct has formed. A thermal inversion is an atmospheric condition where warmer air exists in a well-defined layer above a layer of significantly cooler air. This temperature inversion is the opposite of what is normally the case; air is usually warmer close to the surface, and cooler higher up. In calm weather, a layer of significantly warmer air can rest over colder dense air, forming an atmospheric duct which acts like a refracting lens, producing a series of both inverted and erect images.
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The reduced eye is an idealized model of the optics of the human eye. Introduced by Franciscus Donders, the reduced eye model replaces the several refracting bodies of the eye (the cornea, lens, aqueous humor, and vitreous humor) are replaced by an ideal air/water interface surface that is located 20 mm from a model retina. This, converts a system with six cardinal points (two focal points, two principal points and two nodal points) into one with three cardinal points (two focal points and one nodal point). The reduced eye model is used by medical students when studying refractive errors such as myopia and hyperopia (near- and far-sightedness) and by ophthalmologists to simplify corrective lens computations.
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Wall's aptitude for engineering won him an apprenticeship with Vickers Armstrong at the age of sixteen in the town of Crayford where he was born. He served in the army with the Royal Electrical and Mechanical Engineers in early 1950s and there became interested in telescopes and astronomy. He went on to become a design engineer at Vickers and, while working there in 1969, came up with the idea for an accurate mechanically simple eyepiece mount for amateur telescopes, the Crayford focuser. He is also known for designing dialyte based refracting telescopes, coming up with the Zerochromat retrofocally corrected refractor, including a folded 30-inch f/12 version he built in 1999.
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Rutgers named the building after New York City businessman, Daniel S. Schanck, who donated a large portion of the funds to construct and equip the observatory. The cost of cost of construction and equipment amounted to US$6,166 (2013: US$86,845.07), of which US$2,400 (2013: US$33,802.82) was donated by Schanck (1812–1872). Rutgers equipped the observatory with "a 6.5-inch equatorial refracting telescope, a meridian circle with four-inch object glass for transit observations, a sidereal clock, a mean solar clock...chronograph, repeating circle, and other instruments." The Schanck Observatory served as the university's first astronomical facility and was used to provide instruction to its students through the nineteenth and early twentieth century.
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Treptow telescope (aka Himmelskanone) did away with a dome, and the telescope tube extends above the building in this image Grande Lunette of Nice Observatory of 1886, with 76 cm aperture James Lick telescope of 1888, with 91 cm aperture Great refractor refers to a large telescope with a lens, usually the largest refractor at an observatory with an equatorial mount. The preeminence and success of this style in observational astronomy defines an era in modern telescopy in the 19th and early 20th century. Great refractors were large refracting telescopes using achromatic lenses (as opposed to the mirrors of reflecting telescopes). They were often the largest in the world, or largest in a region.
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A transit of Venus occurred on 8 December 1874 and 6 December 1882. The Transit of Venus Commission set up stations to observe the event. Durban was considered as a possible station but rejected because of tendency to cloudy weather in Natal during December season. Establishing an observatory in Durban was of interest to Harry Escombe, the Durban representative on the Legislative Council of the Colony of Natal. David Gill, Astronomer Royal to the Cape, agreed and £350 voted by the Corporation of Durban plus £500 by the Legislative Council to found an observatory. A Grubb 8-inch aperture equatorial refracting telescope presented by Escombe and a 3-inch transit instrument was purchased by the government.
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Swasey Observatory at Denison University In 1885 Swasey completed work at McCormick Observatory on the 45-foot dome, which was the largest in the world, and had a unique, 3 shutter design. In 1887 Swasey built the mount for the 36-inch refracting telescope at Lick Observatory. In 1898 he manufactured a dividing engine for the U.S. Naval Observatory that was used to make the meridian circles. Both the building and dome of the Dominion Astrophysical Observatory were made by Warner and Swasey Co. Other observatory telescopes and components were built by the company at the Kenwood Observatory, Yerkes Observatory, Argentine National Observatory, the Swasey Observatory at Denison University, and the Case School of Applied Science Observatory.
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Under the microscope the spherulites are of circular outline and are composed of thin divergent fibers that are crystalline as verified with polarized light. Between crossed Nicols, a black cross appears in the spherulite; its axes are usually perpendicular to one another and parallel to the crosshairs; as the microscope stage is rotated the cross remains steady; between the black arms there are four bright sectors. This shows that the spherulite consists of radiate, doubly refracting fibers that have a straight extinction; the arms of the black cross correspond to those fibers that are extinguished. The aggregate is too fine-grained to directly determine what minerals it is composed of using visible light microscopy.
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M 42 in his catalogue Messier's occupation as a comet hunter led him to continually come across fixed diffuse objects in the night sky which could be mistaken for comets. He compiled a list of them, in collaboration with his friend and assistant Pierre Méchain (who may have found at least 20 of the objects), to avoid wasting time sorting them out from the comets they were looking for. The entries are now known to be 39 galaxies, 4 planetary nebulae, 7 other types of nebulae, and 55 star clusters. Messier did his observing with a 100 mm (four-inch) refracting telescope from Hôtel de Cluny (now the Musée national du Moyen Âge), in downtown Paris, France.
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George Ellery Hale (June 29, 1868 - February 21, 1938) was an American solar astronomer, best known for his discovery of magnetic fields in sunspots, and as the leader or key figure in the planning or construction of several world- leading telescopes; namely, the 40-inch refracting telescope at Yerkes Observatory, 60-inch Hale reflecting telescope at Mount Wilson Observatory, 100-inch Hooker reflecting telescope at Mount Wilson, and the 200-inch Hale reflecting telescope at Palomar Observatory. He also played a key role in the foundation of the International Union for Cooperation in Solar Research and the National Research Council, and in developing the California Institute of Technology into a leading research university.
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Hyeronymus Sirturus (Girolamo Sirtori) was a Milanese Jesuit scholar who wrote at least two books on politics and telescopes between 1614 and 1618. The Compendium politicum: ex universa civili doctrina Justi Lipsii pro principatu, tum ex Notis integra fide concinnatum was published by Persius in Frankfurt in 1614.., and the Telescopium: sive ars perficiendi novum illud Galilaei virorium instrumentum ad sydera, by Paul Jacob in 1618 His Telescopium book was written around 1612, only 4 years after the telescope was invented. The book contained a complete set of instructions and diagrams for building a refracting telescope. Sirtori pointed out that "a workman had to be most careful in polishing otherwise the lens became lopsided or aspherical with peripheral distortion".
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The experiment involved repetitively throwing at random a fine steel wire onto a plane wooden surface ruled with equidistant parallel lines. Pi was computed as 2ml/an where m is the number of trials, l is the length of the steel wire, a is the distance between parallel lines, and n was the number of intersections. This paper, an experiment on the Buffon's needle problem, is a very early documented use of random sampling (which Nicholas Metropolis would name the Monte Carlo method during the Manhattan Project of World War II) in scientific inquiry. In 1875 Hall was given responsibility for the USNO 26-inch (66-cm) telescope, the largest refracting telescope in the world at the time.
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Most optical traps operate with a Gaussian beam (TEM00 mode) profile intensity. In this case, if the particle is displaced from the center of the beam, as in the right part of the figure, the particle has a net force returning it to the center of the trap because more intense beams impart a larger momentum change towards the center of the trap than less intense beams, which impart a smaller momentum change away from the trap center. The net momentum change, or force, returns the particle to the trap center. If the particle is located at the center of the beam, then individual rays of light are refracting through the particle symmetrically, resulting in no net lateral force.
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The refractor telescope made by Henry and Gautier became operational around 1886–1887,British university observatories, 1772–1939 By Roger Hutchins;page 252 was the largest in a privately funded observatory, and the first at such high altitude ( above sea level). It was slightly bigger in aperture, several metres longer, and located at a higher altitude than the new (1895) at Pulkovo observatory in the Russian Empire, and the at Vienna Observatory (completed early 1880s).The Observatory, "Large Telescopes", Page 248 In the records for the largest refracting telescopes all three were outperformed by the refractor installed at the Lick Observatory at 1,283 m altitude in 1889. As a scientific institution, the Nice Observatory no longer exists.
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Galileo Galilei, the discoverer of Io The first reported observation of Io was made by Galileo Galilei on 7 January 1610 using a 20x-power, refracting telescope at the University of Padua. However, in that observation, Galileo could not separate Io and Europa due to the low power of his telescope, so the two were recorded as a single point of light. Io and Europa were seen for the first time as separate bodies during Galileo's observations of the Jovian system the following day, 8 January 1610 (used as the discovery date for Io by the IAU). The discovery of Io and the other Galilean satellites of Jupiter was published in Galileo's Sidereus Nuncius in March 1610.
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Edward Joshua Cooper The Signature of Edward Joshua Cooper Edward Joshua Cooper (May 1798 – 23 April 1863) was an Irish landowner, politician and astronomer from Markree Castle in County Sligo. He sat in the House of Commons of the United Kingdom from 1830 to 1841 and from 1857 to 1859, but is best known for his astronomy, and as the creator of Markree Observatory. His observatory was home to the largest refracting (telescope with a lens) of the 1830s (an almost 14 inch astronomical grade Cauchoix of Paris lens, the largest in the World), and the asteroid 9 Metis was discovered there in the 1840s by his assistant. Several astronomical catalogs were also produced in the 19th century there.
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Virtual periscope is a system that allows submerged submarines to observe the surface above them without having to come to a shallower depth, as is required by traditional periscopes. The system that was tested in 2005, actually described in a patent as "Virtual Periscope", aboard USS Chicago (SSN-721) employed a small camera mounted on the sail of the submarine uses the surface of the ocean as a lens, collecting light from above the surface and refracting it below. High-speed signal processing software assembles an image of what is on the surface. The system's resolution did not allow at the time ship identification, only indicating that something is on the surface.
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Examples of such techniques include particle systems (which can simulate rain, smoke, or fire), volumetric sampling (to simulate fog, dust and other spatial atmospheric effects), caustics (to simulate light focusing by uneven light- refracting surfaces, such as the light ripples seen on the bottom of a swimming pool), and subsurface scattering (to simulate light reflecting inside the volumes of solid objects, such as human skin). The rendering process is computationally expensive, given the complex variety of physical processes being simulated. Computer processing power has increased rapidly over the years, allowing for a progressively higher degree of realistic rendering. Film studios that produce computer-generated animations typically make use of a render farm to generate images in a timely manner.
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The observatory facility houses two main telescopes: one 20-inch reflector used primarily for public outreach, and a 32-inch reflector used for teaching and research. It also houses a five-inch solar telescope and an eight-inch refracting telescope. The 32-inch telescope is tied with the Austin-Fellows telescope of the Stull Observatory at Alfred University for being the 2nd-largest optical telescope in the state of New York, the largest being the 40-inch reflector at SUNY Oneonta College Observatory. On its exterior the observatory is covered in aluminum sheathing, making the structure less of a heat polluter than its predecessor whose masonry walls absorbed a lot of daytime solar heat.
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Newall was a keen astronomer, and he commissioned Thomas Cooke to build a telescope for his private observatory at Ferndene, his Gateshead residence. For many years, the 25 inch refracting telescope was the largest in the world, and it was gifted to the Cambridge Observatory after his death in 1889. By the end of the 1950s, the telescope had fallen into disuse, and in 1958 it was donated to the National Observatory of Athens and it was placed at the Penteli Astronomical Station, just north of the city of Athens. He was elected a fellow of the Royal Astronomical Society in 1864, of the Royal Society in 1875, and became in 1879 a member of the Institute of Mechanical Engineers.
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Incident light reflects at the same angle (black lines), but a small portion of the light is refracted as coloured light (red and blue lines). Physicists have been looking at the solar spectrum since Isaac Newton first used a simple prism to observe the refractive properties of light. In the early 1800s Joseph von Fraunhofer used his skills as a glass maker to create very pure prisms, which allowed him to observe 574 dark lines in a seemingly continuous spectrum. Soon after this, he combined telescope and prism to observe the spectrum of Venus, the Moon, Mars, and various stars such as Betelgeuse; his company continued to manufacture and sell high-quality refracting telescopes based on his original designs until its closure in 1884.
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In the case of optical image sampling, as by image sensors in digital cameras, the anti-aliasing filter is also known as an optical low-pass filter (OLPF), blur filter, or AA filter. The mathematics of sampling in two spatial dimensions is similar to the mathematics of time-domain sampling, but the filter implementation technologies are different. The typical implementation in digital cameras is two layers of birefringent material such as lithium niobate, which spreads each optical point into a cluster of four points. The choice of spot separation for such a filter involves a tradeoff among sharpness, aliasing, and fill factor (the ratio of the active refracting area of a microlens array to the total contiguous area occupied by the array).
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He contributed to other scientific journals, and made an immense number of contributions to the Australian press. chromolithograph by Trouvelot In 1872 a equatorial refracting scope was purchased for the observatory, in 1881 Tebbutt discovered another great comet, now designated C/1881 K1, and in 1886 a new telescope of aperture and focal length was purchased, which enabled him to considerably extend his operations. He published in 1887 History and description of Mr. Tebbutt's observatory, Windsor, New South Wales, and followed this with a yearly Report for about 15 years. Between 1868 and 1902 he made 396 lunar occultation observations. A branch of the British Astronomical Association was established at Sydney in 1895 and Tebbutt was elected its first president.
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Europa, along with Jupiter's three other large moons, Io, Ganymede, and Callisto, was discovered by Galileo Galilei on 8 January 1610, and possibly independently by Simon Marius. The first reported observation of Io and Europa was made by Galileo on 7 January 1610 using a 20×-magnification refracting telescope at the University of Padua. However, in that observation, Galileo could not separate Io and Europa due to the low magnification of his telescope, so that the two were recorded as a single point of light. The following day, 8 January 1610 (used as the discovery date for Europa by the IAU), Io and Europa were seen for the first time as separate bodies during Galileo's observations of the Jupiter system.
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Because of their limited light-gathering capability, small telescopes are usually not well- suited to spectroscopy, although some useful spectroscopic work can be performed with reflecting telescopes with a primary mirror as small as when equipped with the increasingly sophisticated CCD imaging and spectroscopic instrumentation that has become available to amateur astronomers in the 21st century. Most telescopes within the field of amateur astronomy are considered to be small, ranging in general from achromatic refracting types, to reflecting telescopes featuring primary mirrors up to or more in diameter. Most small telescopes are dedicated to visual observation, although many are used for astrophotography or to gather scientific data. The range of amateur astronomers' telescopes is wide, with numerous types and designs.
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They are used for various outdoor activities such as birdwatching and other naturalist activities, for hunting and target shooting to verify a marksman's shot placements, for tactical ranging and surveillance, and for any other application that requires more magnification than a pair of binoculars, typically on the order of 20× to 60×. The light-gathering power and resolution of a spotting scope is determined by the diameter of the objective lens, typically between . The larger the objective, the more massive and expensive the telescope. The optical assembly has a small refracting objective lens, an image erecting system that uses either image erecting relay lenses or prisms (Porro prisms or roof prisms), and an eyepiece that is usually removable and interchangeable to give different magnifications.
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The first HH object was observed in the late 19th century by Sherburne Wesley Burnham, when he observed the star T Tauri with the refracting telescope at Lick Observatory and noted a small patch of nebulosity nearby. It was thought to be an emission nebula, later becoming known as Burnham's Nebula, and was not recognized as a distinct class of object. T Tauri was found to be a very young and variable star, and is the prototype of the class of similar objects known as T Tauri stars which have yet to reach a state of hydrostatic equilibrium between gravitational collapse and energy generation through nuclear fusion at their centres. Fifty years after Burnham's discovery, several similar nebulae were discovered with almost star-like appearance.
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Refracting telescopes first appeared in the Netherlands in 1608, apparently the product of spectacle makers experimenting with lenses. The inventor is unknown but Hans Lippershey applied for the first patent, followed by Jacob Metius of Alkmaar.galileo.rice.edu The Galileo Project > Science > The Telescope by Al Van Helden "The Hague discussed the patent applications first of Hans Lipperhey of Middelburg, and then of Jacob Metius of Alkmaar... another citizen of Middelburg, Sacharias Janssen had a telescope at about the same time but was at the Frankfurt Fair where he tried to sell it" Galileo was one of the first scientists to use this new tool for his astronomical observations in 1609. The reflecting telescope was described by James Gregory in his book Optica Promota (1663).
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Telescope dome, seen from Lindenhof hill Urania's refracting telescope is equipped with a Fraunhofer two-lens system of 30 cm aperture and focal length of 5.05 meters, allowing maximal 600-fold magnification (mostly used 150- to 205-fold magnification).Urania observatory: Telescope The refractor in the dome area is the center of the imposing tower building: The telescope stands on a pillar, contact-free installed through the center of the building to the foundations of the business house Urania, fitted with anti-vibration installations.Swissinfo (September 19, 2004): «Offener Himmel» an langer Nacht der Sterne Its optical telescope measures twelve tons and was designed by Carl Zeiss AG in Jena, Germany, considered as a technical masterpiece. Urania's refractor topped technological history as "Urania type".
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All appearances and phenomena are a dream or thoughtform, inter- and intra- reflecting and refracting jewels and mirrors of possibility and potentiality, "arising in relationships" or "dependent co- arising". These lineages hold it and due to the realisations of the sadhana, that the dream of life and regular nightly dreams are not dissimilar, and that in their quintessential nature are non-dual. The non-essential difference between the general dreaming state and the general waking experience is that the latter is generally more concrete and linked with attachments, saṅkhāra and skandha; whereas, standard non-lucid dreaming is ephemeral and transient, and generally culturally reinforced as baseless and empty. In Dream Yoga, living may become the dream, and the dream may become the living.
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Hayden is infamous for being the perpetrator of the Nightmare of Norse Scott, an incident where he murdered several people, including many of his wartime squad mates and Olivier's father, before being apprehended. Many details about the incident, including the fact that his rampage was caused by dangerous Extension experiments performed on the Tindalos members, were covered up over the years to preserve the public's opinion on Extension technology. Gondry's Over-Extended body is specifically designed for stealthy assassinations and is only vaguely humanoid, featuring a head with two faces mounted on thin limbs and a cloak of light-refracting camouflage plates, which allow him to cloak and disguise himself. ; : :A young immigrant man who has illegal extensions so that he can work at construction sites to support his family.
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The beginning of the 20th century saw the worldwide construction of refracting telescopes and sophisticated large reflecting telescopes specifically designed for photographic imaging. Towards the middle of the century, giant telescopes such as the Hale Telescope and the Samuel Oschin telescope at Palomar Observatory were pushing the limits of film photography. Some progress was made in the field of photographic emulsions and in the techniques of forming gas hypersensitization, cryogenic cooling, and light amplification, but starting in the 1970s after the invention of the CCD, photographic plates were gradually replaced by electronic imaging in professional and amateur observatories. CCD's are far more light sensitive, do not drop off in sensitivity over long exposures the way film does ("reciprocity failure"), have the ability to record in a much wider spectral range, and simplify storage of information.
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Eyeshine from retroreflectors of the transparent sphere type is clearly visible in this cat's eyes Another common type of retroreflector consists of refracting optical elements with a reflective surface, arranged so that the focal surface of the refractive element coincides with the reflective surface, typically a transparent sphere and (optionally) a spherical mirror. In the paraxial approximation, this effect can be achieved with lowest divergence with a single transparent sphere when the refractive index of the material is exactly one plus the refractive index ni of the medium from which the radiation is incident (ni is around 1 for air). In that case, the sphere surface behaves as a concave spherical mirror with the required curvature for retroreflection. In practice, the optimal index of refraction may be lower than due to several factors.
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In 1896, Wellesley College physics professor Sarah Frances Whiting met trustee Sarah Elizabeth Whitin at a traditional college ceremony, "Float Night." The conversation turned to a 12" refracting telescope Whiting had used that was being offered for sale, and as told in Wellesley College 1875–1975: A Century of Women: It quickly became apparent that the Observatory would need to be expanded. Sarah Frances Whiting wrote in Whitin's obituary "An Appreciation," which appeared in The Wellesley College News According to Wellesley records, in 1942, before the U.S. entered World War II, "astronomy professor Helen Dodson and Barbara McCarthy, professor of Greek, teach a secret course in cryptography to (at least) ten students. The course was taught evenings at the Observatory, where late-night activity would not attract attention.
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Six stage Steinheill refracting telescope installed at the Mannheim Observatory in 1859. Photo circa 1900–1920 In 1859 Eduard Schönfeld was appointed Director with a salary. The observatory equipment at his disposal was somewhat antiquated, his largest telescope being a small refractor of 73 lines aperture, but he selected a line of work to suit the instruments at his disposal, observing Nebulae, for which he soon made a name for himself, and variable stars and keeping a watch on comets and new planets. The results of his observations of nebulae are contained in two catalogues published in the Astronomische Beobachtungen der Grossherzoglichen Sternwarte zu Mannheim, 1st and 2nd parts (1862 and 1875), and those of his variable star observations appeared in the Jahresberichte des Mannheimer Vereins für Naturkunde, Nos.
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Stratton, 1941, p.280. If the medium is magnetically isotropic but electrically non-isotopic (like a doubly-refracting crystal), the magnetic vectors B and H are still parallel, and the electric vectors E and D are still perpendicular to both, and the ray direction is still perpendicular to E and the magnetic vectors, and the wave-normal direction is still perpendicular to D and the magnetic vectors; but there is generally a small angle between the electric vectors E and D, hence the same angle between the ray direction and the wave-normal direction (Fig.1).Born & Wolf, 1970, p.668. Hence D, E, the wave-normal direction, and the ray direction are all in the same plane, and it is all the more natural to define that plane as the "plane of polarization".
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Reflecting telescopes, though not limited by the color problems seen in refractors, were hampered by the use of fast tarnishing speculum metal mirrors employed during the 18th and early 19th century—a problem alleviated by the introduction of silver coated glass mirrors in 1857, and aluminized mirrors in 1932. The maximum physical size limit for refracting telescopes is about 1 meter (40 inches), dictating that the vast majority of large optical researching telescopes built since the turn of the 20th century have been reflectors. The largest reflecting telescopes currently have objectives larger than 10 m (33 feet), and work is underway on several 30-40m designs. The 20th century also saw the development of telescopes that worked in a wide range of wavelengths from radio to gamma-rays.
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There are claims Leonard Digges independently invented the reflecting telescope, and/or the refracting telescope as part of his need to see accurately over long distances during his surveying works. In the preface to the 1591 Pantometria, (a book on measurement, partially based on his father's notes and observations) Leonard's son Thomas lauded his father's accomplishments. Some of the praise of the son for the father appears to be extravagant exaggeration, while other claims appear more credible. On the fifth page of the preface, Thomas Digges provides a remarkable account of his father's accomplishments: > [H]is divine mind aided with this science of Geometrical mensurations, found > out the quantities, distances, courses, and strange intricate miraculous > motions of these resplendent heavenly Globes of Sun, Moon, Planets and > Stares fixed, leaving the rules and precepts thereof to his posterity.
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Refracting telescopes would quadruple in size by the end of the century, culminating with the largest practical refractor ever built, the Yerkes Observatory 40-inch (1 meter) aperture of 1895. This great refractor pushed the limits of technology of the day; the fabrication of the two element achromatic lens (the largest lens ever made at the time), required 18 attempts and cooperation between Alvan Clark & Sons and Charles Feil of Paris. To achieve its optical aperture it was actually slightly bigger physically, at 41 3/8 in. Refractors had reached their technological limit; the problems of lens sagging from gravity meant refractors would not exceed around 1 meter,Physics Demystified By Stan Gibilisco, , page 515 Since a lens can only be held in place by its edge, the center of a large lens will sag due to gravity, distorting the image it produces.
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Noble is supposed to have said, > The theory (meteoric)... has been already three times killed by Dr Huggins > in England, Dr Vogel in Germany and Professor Keeler at Lick observatory, > and I think that we must look on Mr Naegamvala as having finally killed and > buried it. He was a member of British scientific team that went to Norway, in 1896, to observe a total solar eclipse. The six-inch refracting telescope, from Lerebours and Secretan, of 1850, was remodelled and installed for daily photographs of the Sun and is still being used (one of the oldest telescopes still in use) sent by Greenwich on permanent loan to the photoheliograph. These observations produced plots showing that the shape of the Sun's corona, with respect to sun spot numbers over the years, varies with the solar cycle.
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142, October 1989 Paul Simons, in an article entitled "Weather Secrets of Miracle at Fátima", stated that it is possible that some of the optical effects at Fátima may have been caused by a cloud of dust from the Sahara."Weather Secrets of Miracle at Fátima", Paul Simons, The Times, 17 February 2005. Skeptical investigator Joe Nickell wrote that the "dancing sun" effects reported at Fátima were "a combination of factors, including optical effects and meteorological phenomena, such as the sun being seen through thin clouds, causing it to appear as a silver disc. Other possibilities include an alteration in the density of the passing clouds, causing the sun’s image to alternately brighten and dim and so seem to advance and recede, and dust or moisture droplets in the atmosphere refracting the sunlight and thus imparting a variety of colors".
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Through his career T. W. Webb served as a clergyman at various places including Gloucester, and finally in 1852 was assigned to the parish of Hardwicke in Herefordshire near the border with Wales. In addition to serving faithfully the members of his parish, T. W. Webb pursued astronomical observation in his spare time. On the grounds of the vicarage or parsonage he built a small canvas and wood observatory that was home to instruments including a small 3.7" (94mm) refracting telescope. Webb acquired progressively larger refractors and reflectors, the largest was a 9-1/3" (225mm) aperture silver on glass reflector used from 1866 until his last observation in March 1885. It was at Hardwick that he wrote his classic astronomical observing guide Celestial Objects for Common Telescopes in 1859 for which he is best known today.
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This was the start of the optical industry of grinding and polishing lenses for these "spectacles", first in Venice and Florence in the thirteenth century,"The Galileo Project > Science > The Telescope" by Al Van Helden . Galileo.rice.edu. Retrieved 2012-06-10. and later in the spectacle making centres in both the Netherlands and Germany. Spectacle makers created improved types of lenses for the correction of vision based more on empirical knowledge gained from observing the effects of the lenses rather than using the rudimentary optical theory of the day (theory which for the most part could not even adequately explain how spectacles worked). This practical development, mastery, and experimentation with lenses led directly to the invention of the compound optical microscope around 1595, and the refracting telescope in 1608, both of which appeared in the spectacle making centres in the Netherlands.
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Tourists flock to the Observatory museum, 2009 The observatory buildings at Greenwich became a museum of astronomical and navigational tools, which is part of the Royal Museums Greenwich. Notable exhibits include John Harrison's sea watch, the H4, which received a large reward from the Board of Longitude, and his three earlier marine timekeepers; all four are the property of the Ministry of Defence. Many additional horological artefacts are displayed, documenting the history of precision timekeeping for navigational and astronomical purposes, including the mid-20th-century Russian-made F.M. Fedchenko clock (the most accurate pendulum clock ever built in multiple copies). It also houses the astronomical instruments used to make meridian observations and the 28-inch equatorial Grubb refracting telescope of 1893, the largest of its kind in the UK. The Shepherd Clock outside the observatory gate is an early example of an electric slave clock.
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A rhombicuboctahedron drawn by Leonardo da Vinci, 1509, four centuries before Escher Escher's interest in geometry is well known, but he was also an avid amateur astronomer, and in the early 1940s he became a member of the Dutch Association for Meteorology and Astronomy. He owned a 6 cm refracting telescope, and recorded several observations of binary stars. The use of polyhedra to model heavenly bodies can be traced back to Plato, who in the Timaeus identified the regular dodecahedron with the shape of the heavens and its 12 faces with the constellations of the zodiac.. Later, Johannes Kepler theorized that the distribution of distances of the planets from the sun could be explained by the shapes of the five Platonic solids, nested within each other. Escher kept a model of this system of nested polyhedra, and regularly depicted polyhedra in his artworks relating to astronomy and other worlds.
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Accessed on line 9 June 2013.Notes file for the WDS , WDS Catalog United States Naval Observatory. Accessed on line 9 June 2013.References and discoverer codes, The Washington Double Star Catalog , United States Naval Observatory. Accessed on line 9 June 2013. These double star observations were all made roughly between December 1827 and December 1828, being observed through his homemade 9-foot 23 cm (9-inch) speculum Newtonian reflector, or by measuring the separated distances and position angles of selected double stars using the small equatorial mounted refracting telescope. Most of these pairs have proved to be uninteresting to astronomers, and many of the double stars selected were too wide for the indication of orbital motion as binary stars. It seems these observations were made when the atmospheric conditions were quite unsuitable for looking at deep sky objects, either being made under unsteady astronomical seeing or when the sky was illuminated by the bright moon.
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At the end of a memoir on stress-induced birefringence read in September 1822, Fresnel proposed an experiment, involving a Fresnel rhomb, for the purpose of verifying that optical rotation is a form of birefringence. This experiment, like the one he had just performed on stress-induced birefringence, required a row of prisms with their refracting angles in alternating directions, with two half-prisms at the ends, making the whole assembly rectangular. Fresnel predicted that if the prisms were cut from monocrystalline quartz with their optic axes aligned along the row, and with alternating directions of optical rotation, an object seen by looking along the common optic axis would give two images, which would seem unpolarized if viewed through an analyzer alone; but if viewed through a Fresnel rhomb, they would be polarized at ±45° to the plane of reflection. Confirmation of this prediction was reported in a memoir submitted in December 1822, in which Fresnel coined the terms linear polarization, circular polarization, and elliptical polarization.
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It was during this time that she met Ramón María Aller, the founder and director of the Astronomical Observatory of the USC, and the person who made it possible for her to become the first female Galician astronomer. In that observatory, Ferrín started to use the passage instrument and the refracting telescope, which allowed her to visualize the concealment of stars by the moon, the passage of stars through two verticals, or micrometric measurements of double stars. The results of these investigations were published in the Spanish magazine of astronomy, Urania. Ferrín recalled anecdotally that it was really cold while she was doing her research in the observatory. She never wore trousers because, according to her, it was a piece of clothing that “was not considered feminine and only the more daring movie actresses wore them on the big screen.” In 1950, she received a scholarship from the Spanish National Research Council to conduct research in the Astronomical Observatory of Santiago.
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Sanderson's vision for the future of schools can be seen from an address that he delivered at the University of Leeds: This vision can be compared to the building program that Sanderson undertook at Oundle over the years, which comprised the construction of laboratories, workshops, metalwork and woodwork shops, a forge, a foundry, botanical gardens, a meteorological station, an experimental farm, a drawing office, an observatory, and a library. The observatory was constructed the year before Sanderson died, 1921, on a school playing field, the Home Close, near to the centre of Oundle town, to house a Cooke refracting telescope that had been presented to the school by W. T. Carr MP, an old boy of the school. The museum was intended to be a "Temple of Vision", containing exhibits that illustrated the progress of humanity, and diagrams and charts of history. Its construction was funded by Sir Alfred Fernandez Yarrow, who like Sanderson had lost a son (Eric Yarrow, an Oundelian) in World War 1.
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Crown flash is a rarely observed meteorological phenomenon involving "The brightening of a thunderhead crown followed by the appearance of aurora-like streamers emanating into the clear atmosphere". The current hypothesis for why the phenomenon occurs is that much like the sun dog phenomenon sunlight is reflecting off or refracting through tiny ice crystals though unlike sun dogs crown flash ice crystals are found above the crown of a cumulonimbus cloud. These ice crystals are aligned by the strong electric field effects around the cloud, so the effect may appear as a tall streamer (with a curved shape at times), pillar of light, or resemble a massive flash of a searchlight/flashlight beam through the clouds. When the electric field is disturbed by electrical charging or discharging (typically, lightning flashes) within the cloud, the ice crystals are re-orientated causing the light pattern to shift in a characteristic manner, at times very rapidly and appearing to 'dance' in a strikingly mechanical fashion.
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The Messier catalogue comprises nearly all the most spectacular examples of the five types of deep-sky object – diffuse nebulae, planetary nebulae, open clusters, globular clusters, and galaxies – visible from European latitudes. Furthermore, almost all of the Messier objects are among the closest to Earth in their respective classes, which makes them heavily studied with professional class instruments that today can resolve very small and visually spectacular details in them. A summary of the astrophysics of each Messier object can be found in the Concise Catalog of Deep-sky Objects. Since these objects could be observed visually with the relatively small-aperture refracting telescope (approximately 100 mm, or 4 inches) used by Messier to study the sky, they are among the brightest and thus most attractive astronomical objects (popularly called deep-sky objects) observable from Earth, and are popular targets for visual study and astrophotography available to modern amateur astronomers using larger aperture equipment.
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Hans Lipperhey is known for the earliest written record of a refracting telescope, a patent he filed in 1608.The History of the Telescope By Henry C. King, page 30Light Years: An Exploration of Mankind's Enduring Fascination with Light By Brian Clegg His work with optical devices grew out of his work as a spectacle maker,Fred Watson, Stargazer (page 55) an industry that had started in Venice and Florence in the thirteenth century,galileo.rice.edu The Galileo Project > Science > The Telescope by Al Van Helden and later expanded to the Netherlands and Germany.The History of the Telescope By Henry C. King, page 27, "(spectacles) invention, an important step in the history of the telescope" Lipperhey applied to the States General of the Netherlands on 2 October 1608 for a patent for his instrument "for seeing things far away as if they were nearby",Osservatorio Astronomico di Bologna - TELESCOPES a few weeks before another Dutch instrument-maker's patent, that of Jacob Metius.
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The ability of a curved mirror to form an image may have been known since the time of EuclidReading Euclid by J. B. Calvert, 2000 Duke U. accessed 23 October 2007 and had been extensively studied by Alhazen in the 11th century. Galileo, Giovanni Francesco Sagredo, and others, spurred on by their knowledge that curved mirrors had similar properties to lenses, discussed the idea of building a telescope using a mirror as the image forming objective. Niccolò Zucchi, an Italian Jesuit astronomer and physicist, wrote in his book Optica philosophia of 1652 that he tried replacing the lens of a refracting telescope with a bronze concave mirror in 1616. Zucchi tried looking into the mirror with a hand held concave lens but did not get a satisfactory image, possibly due to the poor quality of the mirror, the angle it was tilted at, or the fact that his head partially obstructed the image.
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Fig.4:Printed label seen through a doubly-refracting calcite crystal and a modern polarizing filter (rotated to show the different polarizations of the two images). Polarization was discovered — but not named or understood — by Christiaan Huygens, as he investigated the double refraction of "Iceland crystal" (transparent calcite, now called Iceland spar). The essence of his discovery, published in his Treatise on Light (1690), was as follows. When a ray (meaning a narrow beam of light) passes through two similarly oriented calcite crystals at normal incidence, the ordinary ray emerging from the first crystal suffers only the ordinary refraction in the second, while the extraordinary ray emerging from the first suffers only the extraordinary refraction in the second. But when the second crystal is rotated 90° about the incident rays, the roles are interchanged, so that the ordinary ray emerging from the first crystal suffers only the extraordinary refraction in the second, and vice versa.
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Nemesis is weakened and extremely vulnerable in its post-Divine Retribution form, so much so that even conventional weapons like missiles can injure it. In the book many believe the dust made from the mirrors have some sort of healing property, however, it is never addressed and is likely that it has no purpose other than refracting light. Nesmsis's wings can also be used for additional defense and they seem to hold up extremely well against the Self-Immolation attacks, the name adopted for the exploding membranes, as witnessed in the final battle of Washington D.C. and the massive self-immolation of Ashtaroth that appeared to kills Nemesis. Nemesis is extremely resilient and has survived all manner of attacks from a GBU-43/B Massive Ordnance Air Blast MOAB strike to the Kaiju Self-Immolation seen in any book whose blast rivals that of several nuclear explosions, to every type of physical attack the Kaiju can throw at her.
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On October 10, 1924, Jiang Bingran, Zhu Kezhen, Gao Lu, and others initiated the establishment of the Chinese Meteorological Society at the Qingdao Observatory, with the purpose of pursuing "progress in meteorological science and development of weather forecasting". In 1925, the observatory built a small domed equatorial chamber on the west side of the observation field and fitted a 16-cm refracting telescope left over from the Germans to observe sunspots; this accumulated China's first batch of sunspot observation data. "Longitude Measurement Monument", established in 1987 to commemorate the observatory's participation in the Longitude Survey of the World In May 1926, Gustav Felier, Chairman of the International Longitude Survey Committee, sent a letter inviting the Qingdao Observatory to participate in the first International Longitude Survey (also known as the Longitude Survey of the World). The Ministry of Education therefore appointed the Qingdao Observatory as the sole representative of Chinese research institutes in the scientific community to participate in the event.
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Doublets In 1861, the brightest star in the night sky, Sirius, was found to have smaller stellar companion using the 18 and half-inch Dearborn refracting telescope. By the 18th century refractors began to have major competition from reflectors, which could be made quite large and did not normally suffer from the same inherent problem with chromatic aberration. Nevertheless, the astronomical community continued to use doublet refractors of modest aperture in comparison to modern instruments. Noted discoveries include the Moons of Mars and a fifth moon of Jupiter, Amalthea. Asaph Hall discovered Deimos on 12 August 1877 at about 07:48 UTC and Phobos on 18 August 1877, at the US Naval Observatory in Washington, D.C., at about 09:14 GMT (contemporary sources, using the pre-1925 astronomical convention that began the day at noon, give the time of discovery as 11 August 14:40 and 17 August 16:06 Washington mean time respectively).Morley, T. A.; A Catalogue of Ground-Based Astrometric Observations of the Martian Satellites, 1877-1982, Astronomy and Astrophysics Supplement Series, Vol.
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Soon after the invention of the refracting telescope Galileo, Giovanni Francesco Sagredo, and others, spurred on by their knowledge that curved mirrors had similar properties as lenses, discussed the idea of building a telescope using a mirror as the image forming objective. The potential advantages of using parabolic mirrors (primarily a reduction of spherical aberration with elimination of chromatic aberration) led to several proposed designs for reflecting telescopes,works by Bonaventura Cavalieri and Marin Mersenne among others have designs for reflecting telescopes the most notable of which was published in 1663 by James Gregory and came to be called the Gregorian telescope, but no working models were built. Isaac Newton has been generally credited with constructing the first practical reflecting telescopes, the Newtonian telescope, in 1668 although due to their difficulty of construction and the poor performance of the speculum metal mirrors used it took over 100 years for reflectors to become popular. Many of the advances in reflecting telescopes included the perfection of parabolic mirror fabrication in the 18th century,Parabolic mirrors were used much earlier, but James Short perfected their construction.
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To Moraima Semprúm de Donahue, "he is a wordsmith, a defender of the oppressed by the policies of the First World and a poet of the heavens"; the one of the blue space and its derivatives ... sky, blue, air, flight, space, clouds, universe, stars, the Pleiades, Scorpio and Sagittarius with its many metaphors that represent parallels: starships, Sputnik, birds, space stations, and Dario's forms of mythological and historical symbols ... He calls himself "pilot of the winds, pilot of the immense and microscopic, pilot of the punished bones" ("The Witness Bares Its Soul/El testigo se desnuda", 9-16). Adriana Corda states "Luis Alberto Ambroggio chooses an invisible power, without land nor identity, as a symbol of a deep cultural malaise at a collective level and responsible for refracting the dantesque domaines at the individual level; he parodizes, he shows the irony, he accuses, he limits ..."Adriana Corda, "La escritura poética de Luis Alberto Ambroggio como resistencia al discurso del poder." XIII Congreso Nacional de Literatura Argentina Facultad de Filosofía y Letras. Universidad Nacional de Tucumán, Agosto 2005. dracorda1.luisalbertoambroggio.com/index.
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U.S. Navy Relocatable Over-the-Horizon Radar station How a skywave OTH radar works: A powerful shortwave signal from a large transmitting antenna (left) reaches a target beyond the horizon by refracting off the ionosphere, and the echo signal from the target (right) returns to the receiving antenna by the same route. Over-the-horizon radar (OTH), sometimes called beyond the horizon (BTH), is a type of radar system with the ability to detect targets at very long ranges, typically hundreds to thousands of kilometres, beyond the radar horizon, which is the distance limit for ordinary radar. Several OTH radar systems were deployed starting in the 1950s and 1960s as part of early warning radar systems, but these have generally been replaced by airborne early warning systems. OTH radars have recently been making a comeback, as the need for accurate long-range tracking becomes less important with the ending of the Cold War, and less-expensive ground-based radars are once again being considered for roles such as maritime reconnaissance and drug enforcement.
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Bourne's is the best description of it, and from his writing it seemed to consist of peering into a large curved mirror that reflected the image produced by a large lens.Patrick Moore, Eyes on the Universe: The Story of the Telescope, Springer Science & Business Media - 2012, page 9 The idea of an "Elizabethan Telescope" has been expanded over the years, including astronomer and historian Colin Ronan concluding in the 1990s that this reflecting/refracting telescope was built by Leonard Digges between 1540 and 1559. This "backwards" reflecting telescope would have been unwieldy, it needed very large mirrors and lens to work, the observer had to stand backwards to look at an upside down view, and Bourne noted it had a very narrow field of view making it unsuitable for military purposes. The optical performance required to see the details of coins lying about in fields, or private activities seven miles away, seems to be far beyond the technology of the timeFred Watson, (2007), Stargazer: The Life and Times of the Telescope, page 40.
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She Remembers Everything received positive reviews from critics. Writing for Rolling Stone, Will Hermes described the album as a "master class in channeling life into song" and added that "Cash is one of the most ambitious and literary songwriters of her generation" who "goes especially deep on this set", describing how "sometimes the songs appear to conjure autobiography, like “Everyone But Me,” which involves the loss of a mother and father" and "other times she puts more distance between self and subject". Of the album's genre, he noted that Cash "remains hard to categorize, refracting country alongside rock, folk and other elements befitting a longtime resident of New York City’s melting pot". Hermes considers "8 God's of Harlem" as the album's "standout" track and also highlights closing track "My Least Favorite Life", describing it as "the album’s dark lodestar" and a " a sweetly grim waltz with an Eastern European lilt, Brechtian existentialism and a little Tom Waits-ian surrealism" and concludes that "in her narrative hands, it’s comforting not to be traveling alone".
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The different angles of refraction for the two polarization components are shown in the figure at the top of the page, with the optic axis along the surface (and perpendicular to the plane of incidence), so that the angle of refraction is different for the polarization (the "ordinary ray" in this case, having its electric vector perpendicular to the optic axis) and the polarization (the "extraordinary ray" with a polarization component along the optic axis). In addition, a distinct form of double refraction occurs in cases where the optic axis is not along the refracting surface (nor exactly normal to it); in this case, the dielectric polarization of the birefringent material is not exactly in the direction of the wave's electric field for the extraordinary ray. The direction of power flow (given by the Poynting vector) for this inhomogenous wave is at a finite angle from the direction of the wave vector resulting in an additional separation between these beams. So even in the case of normal incidence, where the angle of refraction is zero (according to Snell's law, regardless of the effective index of refraction), the energy of the extraordinary ray may be propagated at an angle.
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Treatment is usually surgical, performed at the insertional ends of extraocular muscles (where they attach to the globe). Resection surgery removes tissue in order to stretch a muscle, increasing its elastic force; recession moves an insertion so as to reduce stretch, and so reduce elastic force; transposition moves an insertion “sideways”, sacrificing one direction of muscle action for another; posterior fixation relocates a muscle’s effective insertion to a mechanically disadvantageous position. All are kinds of compensatory impairment. Pharmacologic injection treatments, in contrast, offer the possibility of directly increasing or decreasing contractile muscle strength and elastic stiffness, as well as changing muscle length, without removing tissue or otherwise compromising orbital mechanics. The idea of treating strabismus by cutting some of the extraocular muscle fibers was published in American newspapers by New York oculist John Scudder in 1837 Spherical lenses and miotic eye drops can provide relief in some types of horizontal strabismus by biasing the neural link between convergence (orienting the lines of sight for near objects) and accommodation (focusing), and prism lenses can relieve diplopia (double vision) by refracting the visual axis, but these treatments don’t address the underlying muscular imbalance, and are not further considered here.
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Sasha's primary vendetta with the Adepts is the murder of at the hands of the Aurum (Gold) Qwaser who exiled him with a large scar on the left side of his face shaped like an inverted Eastern Cross that tends to bleed in response to Sasha's excitement during battle -- the acme of which characterized by Sasha's left eye becoming red and the scar glowing prior to bleeding heavily during power-down. Driven by his bitter prologue with the Adepts and the parallels that he sees between Tomo and Olja, Sasha's ferocity reaches its zenith when the Adepts target Tomo for her high- quality soma; during his time with Mafuyu, Sasha comes to realize the infinite value of human life as he demonstrates a copious contempt for the Adepts endangering innocent people. Aside from the comedy of refracting Miyuri's persecution to her detriment and the situational remarks in Russian (though the translation is so-so and the pronunciation is very poor), Sasha is shocked to find that Mafuyu gives as good as she gets when he obdurately ignores the social conventions of human civilization and forces him to partake her consummate cooking -- particularly when it is his favorite dish borscht.
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Gilliss proved himself to be an excellent astronomical observer. In 1837 he was named officer-in-charge of the depot and began an extensive series of observations of the moon and stars for the purpose of longitude determination. In February 1838 he was promoted to lieutenant.Dick (2000) In 1838 Wilkes left the depot to lead the U.S. Exploring Expedition and Gilliss replaced him as head of the organization. Gilliss began a series of celestial observations that were published in 1846 as Astronomical Observations made at the Naval Observatory, Washington. This reference listed some 1,248 stars and was the first star catalog published in the United States.Sterling (1997) Gilliss is most noted for his successful efforts to establish the U.S. Naval Observatory, the first national observatory in the United States. In 1841 he first proposed a new depot and personally lobbied congress for the funds. In 1842 Congress passed an authorization for $25,000 for a new depot and "a small observatory". Gilliss used the funds to equip the new building with astronomical instruments, including a 9.6-inch achromatic refracting telescope, a 5.5-inch transit instrument, a 4-inch meridian circle, and a 5-inch prime vertical telescope.
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Telescopic sights based on refracting telescopes using image erector lenses to present to the user with an upright image have two planes of focus where a reticle can be placed: at the focal plane between the objective and the image erector lens system (the First Focal Plane (FFP)), or the focal plane between the image erector lens system and the eyepiece (the Second Focal Plane (SFP)).Fred A. Carson, Basic optics and optical instruments, page 4-33 On fixed power telescopic sights there is no significant difference, but on variable power telescopic sights a first focal plane reticle expands and shrinks along with the rest of the image as the magnification is adjusted, while a second focal plane reticle would appear the same size and shape to the user as the target image grows and shrinks. In general, the majority of modern variable-power scopes are SFP unless stated otherwise. Every European high-end telescopic sight manufacturer offers FFP reticles on variable power telescopic sights, since the optical needs of European hunters who live in jurisdictions that allow hunting at dusk, night and dawn differ from hunters who traditionally or by legislation do not hunt in low light conditions.
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