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35 mm film is a film gauge used in filmmaking, and the film standard.
The ubiquity of 35 mm movie projectors in commercial movie theaters made 35 mm the only motion picture format that could be played in almost any cinema in the world, until digital projection largely superseded it.
History and development
Early history
thumb|Eastman (L) giving Edison the first roll of movie film, which was 35 mm
In 1880, George Eastman began to manufacture gelatin dry photographic plates in Rochester, New York. Along with W. H. Walker, Eastman invented a holder for a roll of picture-carrying gelatin layer-coated paper. Hannibal Goodwin then invented a nitrocellulose film base in 1887, the first transparent, flexible film. Eastman also produced these components, and his was the first major company to mass-produce such film when, in 1889, Eastman realized that the dry-gelatino-bromide emulsion could be coated onto this clear base, eliminating the paper.
With the advent of flexible film, Thomas Edison quickly set out on his invention, the Kinetoscope, which was first shown at the Brooklyn Institute of Arts and Sciences on May 9, 1893. The Kinetoscope was a film loop system intended for one-person viewing. Edison, along with assistant William Kennedy Dickson, followed that up with the Kinetophone, which combined the Kinetoscope with Edison's cylinder phonograph. Beginning in March 1892, Eastman and then, from April 1893 into 1896, New York's Blair Camera Co. supplied Edison with film stock. Dickson is credited as the inventor of 35 mm movie film in 1889, The company still received film from Blair after this; at first Blair would supply only film stock that would be trimmed and perforated at the Edison lab to create gauge filmstrips, then at some point in 1894 or 1895, Blair began sending stock to Edison that was cut exactly to specification.
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Around 1896, a 35 mm projector known as a "photo-rotoscope" was made by W. C. Hughes in London, which advanced the film by means of a "dog" motion.
For a time, it had been generally assumed that Dickson was following cinematography formats established by Eastman in producing the film, but Eastman had produced film in sheets that were then cut to order.<sup>653</sup>
Edison claimed exclusive patent rights to the design of 35 mm motion picture film, with four sprocket holes (perforations) per frame, forcing his only major filmmaking competitor, American Mutoscope & Biograph, to use a 68 mm film that used friction feed, not sprocket holes, to move the film through the camera. A court judgment in March 1902 invalidated Edison's claim, allowing any producer or distributor to use the Edison 35 mm film design without license. Filmmakers were already doing so in Britain and Europe, where Edison did not file patents. At the time, film stock was usually supplied unperforated and punched by the filmmaker to their standards with perforation equipment. A variation developed by the Lumière brothers used a single circular perforation on each side of the frame towards the middle of the horizontal axis.
Becoming the standard
thumb|Dickson's 35 mm movie film standard (center)
When films began to be projected, several projection devices were unsuccessful and fell into obscurity because of technical failure, lack of business acumen on the part of their promoters, or both. The Vitascope, the first projection device to use 35 mm, was technologically superior and compatible with the many motion pictures produced on 35 mm film. Edison bought the device in 1895–96; the Lumiere's 35 mm projection Cinematograph also premiered in 1895, and they established 35 mm as the standard for exhibition. Scholar Paul C. Spehr describes the importance of these developments: