Polyvision

Polyvision was the name given by the French film critic Émile Vuillermoz to a specialized widescreen film format devised exclusively for the filming and projection of Abel Gance's 1927 film Napoleon. It involved the simultaneous projection of three reels of silent film arrayed in a horizontal row, making for a total aspect ratio of 4:1 (1.33×3:1). This configuration is considered a largely similar precursor to Cinerama, which would debut a quarter of a century later; however, it is unlikely that Polyvision was a direct inspiration for later widescreen techniques, as the triptych sequence of Napoleon was cut from the film by its distributors after only a few screenings and was not seen again until Kevin Brownlow compiled his restorations from the 1970s onwards.

Three film cameras were stacked vertically to shoot the widescreen compositions which would be viewed across all three sections. Gance also used the three strips to create triptych compositions of panels contrasting or simultaneous action, mirrored sides framing the center strip, and perceptual cross-cutting. In this respect, Polyvision can arguably be said to have inspired split screen compositions as well as in-eye edited experiments such as Mike Figgis's Timecode. Gance was unable to eliminate the problem of the two seams dividing the three panels of film as shown on screen, so he avoided the problem by putting three completely different shots together in some of the Polyvision scenes. When Gance viewed Cinerama many years later, he noticed that the widescreen image was still not seamless, that the problem was not entirely fixed.

Polyvision was only used for the final reel of Napoleon, to create a climactic finale. Filming the whole story in Polyvision was impractical as Gance wished for a number of innovative shots, each requiring greater flexibility than was allowed by three interlocked cameras. When the film was severely re-cut by the distributors very early on during exhibition, the new version only retained the center strip in order to allow projection in standard single-projector cinemas. Brownlow's restored version, first seen on 31 August 1979 at the Telluride Film Festival, in Telluride, Colorado, finishes with a flourish intended by Gance: it uses red and blue tinted film on the left and right panels to create le tricolore—the flag of Napoleon's triumphant army.

...
Wikipedia