35mm film format

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 1 3/8 inches or 35 mm wide hence the name. The standard negative pulldown is four perforations per frame along both edges, which makes for exactly 16 frames per foot.

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