35 mm film

35 mm film is the basic film gauge most commonly used for both still photography and motion pictures, and remains relatively unchanged since its introduction in 1892 by William Dickson and Thomas Edison, using film stock supplied by George Eastman. The photographic film is cut into strips 35 millimeters (about 1 3/8 inches) wide — hence the name. The standard negative pulldown for movies ("single-frame" format) is four perforations per frame along both edges, which makes for exactly 16 frames per foot (for stills, the standard frame is eight perforations).
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