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1 Watkins, Alfred
SUBJECT AREA: Photography, film and optics[br]b. 1854 Hereford, Englandd. 7 April 1935 Hereford, England[br]English photographer who developed the first practical exposure-measuring system.[br]His first patent was granted on 27 January 1890 and described a method of measuring the "actinic" value of light as a means of determining exposure. A strip of sensitized paper which darkened on exposure to light was used, and the time taken for it to darken to match a standard tint was measured. This time could be used to calculate the necessary exposure time, taking into account the speed of the plate, shutter speed and aperture. Watkins marketed a number of these actinometer designs, of which the most popular was the Watkins Bee Meter, which was in a pocket-watch form, introduced in 1903 and remaining on sale until 1939. Watkins was concerned that photographers recognize that exposure measurement had to take into account the effect of development time and temperature. In 1893 he devised the concept of the "Watkins Factor": he showed that when plates were developed by inspection, as was the practice at the time, a fixed relationship existed between the time of the first appearance of the image and the total time required to give a fully developed negative. The Watkins Factor was the figure that the first time must be multiplied by to give the second time. Watkins published tables of factors for different brands of plates and for different developers, and marketed various aids such as specially calibrated thermometers and clocks, as aids in using "Fac-torial Development" to give consistent negatives. After the early years of the twentieth century Watkins gave up direct participation in photography and devoted his time to a variety of interests, including the plotting of ley lines in England.BC -
2 Photography, film and optics
See also: INDEX BY SUBJECT AREA[br]Ding HuanGabor, DennisKlic, KarolLippershey, HansMarton, LadislausTournachon, Gaspard FélixBiographical history of technology > Photography, film and optics
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Alfred Watkins — (* 27 de enero de 1855–15 de abril de 1935) fue un anticuario y un arqueólogo amateur, quien en sus recorridos por la Gran Bretaña, creyó observar que las estructuras arqueológicas, como monolitos, iglesias, entre otras formaban líneas rectas en… … Wikipedia Español
Alfred Watkins — (January 27, 1855 ndash; April 15, 1935) was a self taught amateur archaeologist and antiquarian who noticed in the British landscape the apparent arrangement of ancient features along straight lines, known as ley lines. Watkins was born in… … Wikipedia
Watkins (surname) — Watkins is an English and Welsh surname derived as a patronymic from Watkin, in turn a diminutive of the name Watt (also Wat), a popular Middle English given name itself derived as a pet form of the name Walter. It may refer to: *Aaron S. Watkins … Wikipedia
Alfred Eastlack Driscoll — (* 25. Oktober 1902 in Pittsburgh, Pennsylvania; † 9. März 1975) war ein US amerikanischer Politiker und von 1947 bis 1954 Gouverneur des Bundesstaates New Jersey. Inhaltsverzeichnis 1 Frühe Jahre und politischer Aufstieg … Deutsch Wikipedia
Alfred Janes — (1911 February, 1999) was a Welsh artist, best known as a member of the circle of Dylan Thomas and Vernon Watkins.Janes was born in Swansea, and first met Thomas, who was a few years his junior, at Bishop Gore School. A mutual friend was the… … Wikipedia
Alfred E. Driscoll — Alfred Eastlack Driscoll (* 25. Oktober 1902 in Pittsburgh, Pennsylvania; † 9. März 1975) war ein US amerikanischer Politiker und von 1947 bis 1954 Gouverneur des Bundesstaates New Jersey. Inhaltsverzeichnis 1 Frühe Jahre und politischer Aufstieg … Deutsch Wikipedia
Alfred Malherbe — (* 14 de julio de 1804, Metz, isla Mauricio 14 de agosto de 1866, íbid.) fue un magistrado francés, y naturalista amateur. Luego de terminar sus estudios de leyes, es nombrado en el Tribunal de Metz, en 1832. Hizo carrera llegando a juez de… … Wikipedia Español
Alfred Blalock — Born April 5, 1899 Culloden, Georgia, United States Died September 15, 1964(1964 09 15) (aged 65) Education University of Georgia Johns Hopkins Medical School … Wikipedia
Alfred Blalock — (* 5. April 1899 in Culloden, Georgia; † 15. September 1964) war ein US amerikanischer Chirurg. Er wurde insbesondere bekannt durch seine wegweisenden medizinischen Forschungen auf dem Gebiet des traumatischen Schocks und die Blalock Taussig… … Deutsch Wikipedia
Alfred Briggs Irion — (* 18. Februar 1833 bei Evergreen, Avoyelles Parish, Louisiana; † 21. Mai 1903 in New Orleans, Louisiana) war ein US amerikanischer Politiker. Zwischen 1885 und 1887 vertrat er den Bundesstaat Louisiana im US Repräsentantenhaus. Werdegang… … Deutsch Wikipedia
Alfred Rouse — Alfred Arthur Rouse (6 April, 1894At his trial, Rouse declared I have always understood that I was thirty six, but I have no proof of that . See Trial , p. 138.] ndash;10 March, 1931) was a British murderer. It was theorised, though never proved … Wikipedia
