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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