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In motion picture technology—either film or video—high frame rate (HFR) refers to higher frame rates than typical prior practice. The frame rate for motion picture film cameras was typically 24 frames per second with multiple shuttering on each frame to prevent flicker during projection. Television video historically operated at 50 or 60 images per second using interlaced scanning. (A video "frame" is actually two images, hence PAL 25fps looks nothing like film's 24fps.) Frame rates higher than 24 Hz for feature motion pictures and frame rates higher than 30 Hz for other applications is an emerging trend in the 21st century. ==History of frame rates in cinema== In early cinema history, there was no standard frame rate established. Edison's early films were shot at 40 frames per second (fps), while the Lumière Brothers used 16 fps. This had to do with a combination of the use of a hand crank rather than a motor, which created variable frame rates because of the inconsistency of the cranking of the film through the camera. After the introduction of synch sound recording, 24 fps became the industry standard frame rate for capture and projection of motion pictures. 24 fps was chosen because it was the best frame rate for sound clarity – lower frame rates produced sound tracks with too much surface noise. A few film formats have experimented with frame rates higher than the 24 fps standard. The original 3-strip Cinerama features of the 1950s ran at 26 fps. The first two Todd-AO 70mm features, ''Oklahoma!'' (1955) and ''Around the World in 80 Days'' (1956) were shot and projected at 30 fps. Douglas Trumbull's 70mm Showscan film format operated at 60 fps. The IMAX HD (high definition in this case meaning high definition film stock, as 70mm IMAX is the highest resolution motion picture image in the world) film ''Momentum'', presented at Seville Expo '92, was shot and projected at 48 fps. IMAX HD has also been used in ridefilms, including the Disney theme park attraction Soarin' Over California. The proposed Maxivision 48 format ran 35mm film at 48 fps, but was never commercially deployed. Digital Cinema Initiatives has published a document outlining recommended practice for high frame rate digital cinema. This document outlines the frame rates and resolutions that can be used in high frame rate digital theatrical presentations with currently available equipment. 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 frame rate」の詳細全文を読む スポンサード リンク
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