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High-speed photography is the science of taking pictures of very fast phenomena. In 1948, the Society of Motion Picture and Television Engineers (SMPTE) defined high-speed photography as any set of photographs captured by a camera capable of 128 frames per second or greater, and of at least three consecutive frames. High-speed photography can be considered to be the opposite of time-lapse photography. In common usage, high-speed photography may refer to either or both of the following meanings. The first is that the photograph itself may be taken in a way as to appear to freeze the motion, especially to reduce motion blur. The second is that a series of photographs may be taken at a high sampling frequency or frame rate. The first requires a sensor with good sensitivity and either a very good shuttering system or a very fast strobe light. The second requires some means of capturing successive frames, either with a mechanical device or by moving data off electronic sensors very quickly. Other considerations for high-speed photographers are record length, reciprocity breakdown, and spatial resolution. == Early applications and development == The first practical application of high-speed photography was Eadweard Muybridge's 1878 investigation into whether horses' feet were actually all off the ground at once during a gallop. The first photograph of a supersonic flying bullet was taken by the Austrian physicist Peter Salcher in Rijeka in 1886, a technique that was later used by Ernst Mach in his studies of supersonic motion.〔Peter Salcher und Ernst Mach, Schlierenfotografie von Überschall-Projektilen, W. Gerhard Pohl, Universität Wien, PLUS LUCIS 2/2002 - 1/2003 ISSN 1606-3015 (in German)http://www.univie.ac.at/pluslucis/PlusLucis/031/s22.pdf〕 German weapons scientists applied the techniques in 1916.〔The Quarterly of Film, Radio and Television vol 6 no 3, Spring 1952 p235 http://www.jstor.org/pss/1209846〕 Bell Telephone Laboratories was one of the first customers for a camera developed by Eastman Kodak in the early 1930s.〔Kodak High-Speed Camera Type III, September 1944, http://people.rit.edu/andpph/text-eastman-high-speed-camera.html, Eastman Kodak Co.. Retrieved 2 November 2009.〕 Bell used the system, which ran 16 mm film at 1000 frame/s and had a load capacity, to study relay bounce. When Kodak declined to develop a higher-speed version, Bell Labs developed it themselves, calling it the Fastax. The Fastax was capable of 5,000 frame/s. Bell eventually sold the camera design to Western Electric, who in turn sold it to the Wollensak Optical Company. Wollensak further improved the design to achieve 10,000 frame/s. Redlake Laboratories introduced another 16 mm rotating prism camera, the Hycam, in the early 1960s.〔Pendley, Gil (July 2003). Claude Cavailler, Graham P. Haddleton, Manfred Hugenschmidt. ed. "High-Speed Imaging Technology; Yesterday, Today & Tomorrow". ''Proceedings of SPIE'' 4948: 110–113.〕 Photo-Sonics developed several models of rotating prism camera capable of running 35 mm and 70 mm film in the 1960s. Visible Solutions introduced the Photec IV 16 mm camera in the 1980s. In 1940, a patent was filed by Cearcy D. Miller for the rotating mirror camera, theoretically capable of one million frames per second. The first practical application of this idea was during the Manhattan Project, when Berlin Brixner, the photographic technician on the project, built the first known fully functional rotating mirror camera. This camera was used to photograph early prototypes of the first nuclear bomb, and resolved a key technical issue about the shape and speed of the implosion, that had been the source of an active dispute between the explosives engineers and the physics theoreticians. The D. B. Milliken company developed an intermittent, pin-registered, 16 mm camera for speeds of 400 frame/s in 1957.〔 Mitchell, Redlake Laboratories, and Photo-Sonics eventually followed in the 1960s with a variety of 16, 35, and 70 mm intermittent cameras. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「High-speed photography」の詳細全文を読む スポンサード リンク
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