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1 денситометрия
Russian-English dictionary of telecommunications > денситометрия
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2 денситометрия
1) Medicine: densitometry2) Telecommunications: density sensitometry3) Laboratory equipment: densimetry4) Automation: destometry -
3 Hurter, Ferdinand
SUBJECT AREA: Photography, film and optics[br]b. 15 March 1844 Schaffhausen, Switzerlandd. 5 March 1898[br]Swiss chemist who, with Vero Charles Driffield, established the basis of modern sensitometry in England.[br]Ferdinand Hurter worked for three years as a dyer's apprentice before entering the Polytechnic in Zurich; he transferred to Heidelberg, where he graduated in 1866. A year later he secured an appointment as a chemist for the British alkali manufacturing company, Gaskell, Deacon \& Co. of Widnes, Cheshire. In 1871 he was joined at the company by the young engineer Vero Charles Driffield, who was to become his co-worker. Driffield had worked for a professional photographer before beginning his engineering apprenticeship and it was in 1876, when Hurter sought to draw on this experience, that the partnership began. At this time the speed of the new gelatine halide dry plates was expressed in terms of the speed of a wet-collodion plate, an almost worthless concept as the speed of a collodion plate was itself variable. Hurter and Driffield sought to place the study of photographic emulsions on a more scientific basis. They constructed an actinometer to measure the intensity of sunlight and in 1890 published the first of a series of papers on the sensitivity of photographic plates. They suggested methods of exposing a plate to lights of known intensities and measuring the densities obtained on development. They were able to plot curves based on density and exposure which became known as the H \& D curve. Hurter and Driffield's work allowed them to express the characteristics of an emulsion with a nomenclature which was soon adopted by British plate manufacturers. From the 1890s onwards most British-made plates were identified with H \& D ratings. Hurter and Driffield's partnership was ended by the former's death in 1898.[br]Further ReadingW.B.Ferguson (ed.), 1920, The Photographic Researches of Ferdinand Hurter \& Vero C. Driffield, London: Royal Photographic Society reprinted in facsimile, with a new introd. by W.Clark, 1974, New York (a memorial volume; the most complete account of Hurter and Driffield's work, includes a reprint of all their published papers).JW
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Sensitometry — is the scientific study of light sensitive materials, especially photographic film. The study has its origins in the work by Ferdinand Hurter and Vero Charles Driffield (circa 1876) with early black and white emulsions. [Hurter, Ferdinand… … Wikipedia
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characteristic curve — Photog. a graph used in sensitometry to show the relationship between exposure time and image density under constant developing conditions. Also called sensitometric curve. [1900 05] * * * … Universalium
