processed plate

SUBJECT AREA: Photography, film and optics

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Born of French parents, Lippman's work began with a distinguished career in classics, philosophy, mathematics and physics at the Ecole Normale in Luxembourg. After further studies in physics at Heidelberg University, he returned to France and the Sorbonne, where he was in 1886 appointed Director of Physics. He was a leading pioneer in France of research into electricity, optics, heat and other branches of physics.

In 1886 he conceived the idea of recording the existence of standing waves in light when it is reflected back on itself, by photographing the colours so produced. This required the production of a photographic emulsion that was effectively grainless: the individual silver halide crystals had to be smaller than the shortest wavelength of light to be recorded. Lippman succeeded in this and in 1891 demonstrated his process. A glass plate was coated with a grainless emulsion and held in a special plate-holder, glass towards the lens. The back of the holder was filled with mercury, which provided a perfect reflector when in contact with the emulsion. The standing waves produced during the exposure formed laminae in the emulsion, with the number of laminae being determined by the wavelength of the incoming light at each point on the image. When the processed plate was viewed under the correct lighting conditions, a theoretically exact reproduction of the colours of the original subject could be seen. However, the Lippman process remained a beautiful scientific demonstration only, since the ultra-fine-grain emulsion was very slow, requiring exposure times of over 10,000 times that of conventional negative material. Any method of increasing the speed of the emulsion also increased the grain size and destroyed the conditions required for the process to work.

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1) Engineering: processed wafer (полупроводниковая)

2) Polygraphy: processed plate

SUBJECT AREA: Photography, film and optics

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Professor of Physics at Trinity College, Dublin, Joly developed a concept first suggested by Ducos du Hauron, creating in 1893 a process in which fine transparent red, green and blue lines, less than 0.1 mm wide, were ruled on a glass plate. The coloured inks were aniline dyes mixed with gum. This screen plate was held in close contact with a photographic negative plate which was exposed through the screen in a camera. The processed negative was printed onto a positive plate, and a viewing screen, similar to that used for taking, was bound up with it in careful register, to reproduce the original colours. The process was patented in 1894, and marketed in 1895. It was the first commercially successful additive screen-plate process to appear. While the results could be quite acceptable, the inadequate colour sensitivity of the negative plates then available limited the usefulness of this process. Professor Joly's other achievements included geological research and the treatment of cancer by radium.

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SUBJECT AREA: Photography, film and optics

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The young Eastman was a clerk-bookkeeper in the Rochester Savings Bank when in 1877 he took up photography. Taking lessons in the wet-plate process, he became an enthusiastic amateur photographer. However, the cumbersome equipment and noxious chemicals used in the process proved an obstacle, as he said, "It seemed to be that one ought to be able to carry less than a pack-horse load." Then he came across an account of the new gelatine dry-plate process in the British Journal of Photography of March 1878. He experimented in coating glass plates with the new emulsions, and was soon so successful that he decided to go into commercial manufacture. He devised a machine to simplify the coating of the plates, and travelled to England in July 1879 to patent it. In April 1880 he prepared to begin manufacture in a rented building in Rochester, and contacted the leading American photographic supply house, E. \& H.T.Anthony, offering them an option as agents. A local whip manufacturer, Henry A.Strong, invested $1,000 in the enterprise and the Eastman Dry Plate Company was formed on 1 January 1881. Still working at the Savings Bank, he ran the business in his spare time, and demand grew for the quality product he was producing. The fledgling company survived a near disaster in 1882 when the quality of the emulsions dropped alarmingly. Eastman later discovered this was due to impurities in the gelatine used, and this led him to test all raw materials rigorously for quality. In 1884 the company became a corporation, the Eastman Dry Plate \& Film Company, and a new product was announced. Mindful of his desire to simplify photography, Eastman, with a camera maker, William H.Walker, designed a roll-holder in which the heavy glass plates were replaced by a roll of emulsion-coated paper. The holders were made in sizes suitable for most plate cameras. Eastman designed and patented a coating machine for the large-scale production of the paper film, bringing costs down dramatically, the roll-holders were acclaimed by photographers worldwide, and prizes and medals were awarded, but Eastman was still not satisfied. The next step was to incorporate the roll-holder in a smaller, hand-held camera. His first successful design was launched in June 1888: the Kodak camera. A small box camera, it held enough paper film for 100 circular exposures, and was bought ready-loaded. After the film had been exposed, the camera was returned to Eastman's factory, where the film was removed, processed and printed, and the camera reloaded. This developing and printing service was the most revolutionary part of his invention, since at that time photographers were expected to process their own photographs, which required access to a darkroom and appropriate chemicals. The Kodak camera put photography into the hands of the countless thousands who wanted photographs without complications. Eastman's marketing slogan neatly summed up the advantage: "You Press the Button, We Do the Rest." The Kodak camera was the last product in the design of which Eastman was personally involved. His company was growing rapidly, and he recruited the most talented scientists and technicians available. New products emerged regularly—notably the first commercially produced celluloid roll film for the Kodak cameras in July 1889; this material made possible the introduction of cinematography a few years later. Eastman's philosophy of simplifying photography and reducing its costs continued to influence products: for example, the introduction of the one dollar, or five shilling, Brownie camera in 1900, which put photography in the hands of almost everyone. Over the years the Eastman Kodak Company, as it now was, grew into a giant multinational corporation with manufacturing and marketing organizations throughout the world. Eastman continued to guide the company; he pursued an enlightened policy of employee welfare and profit sharing decades before this was common in industry. He made massive donations to many concerns, notably the Massachusetts Institute of Technology, and supported schemes for the education of black people, dental welfare, calendar reform, music and many other causes, he withdrew from the day-to-day control of the company in 1925, and at last had time for recreation. On 14 March 1932, suffering from a painful terminal cancer and after tidying up his affairs, he shot himself through the heart, leaving a note: "To my friends: My work is done. Why wait?" Although Eastman's technical innovations were made mostly at the beginning of his career, the organization which he founded and guided in its formative years was responsible for many of the major advances in photography over the years.

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