Ultra Panavision 70

Ultra Panavision 70 and MGM Camera 65 were, from 1957 to 1966, the marketing brands that identified motion pictures photographed with Panavision's anamorphic movie camera lenses. The 70 mm film gauge actually used 65 mm wide film in the camera to capture images in these processes. The projection print, however, was 70 mm film stock. The extra 5 mm on the positive projection print was used to accommodate six-track stereo sound. Ultra Panavision 70 and MGM Camera 65 were shot at 24 frames per second (fps) using anamorphic camera lenses. Ultra Panavision 70 and MGM Camera 65's anamorphic lenses compressed the image 1.25 times, yielding an extremely wide aspect ratio of 2.76:1 (when a 70 mm projection print was used).

Metro-Goldwyn-Mayer (MGM), like other American motion picture studios, briefly experimented with a variety of widescreen formats in the late 1920s. In 1929, the Fox Film Corporation introduced the Fox Grandeur widescreen photographic system which used a film 70 mm wide and had an aspect ratio of 2.13:1. MGM licensed the Grandeur lens and camera system which they called "Realife" but abandoned the format after just two films, 1930's Billy the Kid and 1931's The Great Meadow. Grandeur used non-standard perforations, but another format developed at around this time by Paramount used 65 mm film with standard perforations, the frame being 5 perforations high. Although these formats failed commercially at the time, the 65 mm film size and cameras built to use it were to form the basis, some two decades later, of the camera format for the new 70 mm formats introduced in the 1950s.

In 1948, a U.S. Supreme Court decision forced movie studios to divest themselves of their profitable theater chains. The loss of these theaters and the competitive pressure of television caused significant financial distress for many American motion picture studios. In 1952 the launch of Cinerama was a public sensation and suggested a way to bring studios back from the financial brink, but the cameras were heavy, bulky, and difficult to use. Installing Cinerama in a theater was no simple matter either, as the system required three projectors, each in its own projection booth, as well as an elaborate 7-channel sound system and a special large, deeply curved, screen.

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