VistaVision is a higher resolution, widescreen variant of the 35mm motion picture film format which was created by engineers at Paramount Pictures in 1954.
Paramount did not use anamorphic processes such as CinemaScope but refined the quality of their flat widescreen system by orienting the 35mm negative horizontally in the camera gate and shooting onto a larger area, which yielded a finer-grained projection print.
As finer-grained film stocks appeared on the market, VistaVision became obsolete. Paramount dropped the format after only seven years, although for another forty years the format was used by some European and Japanese producers for feature films, and by American film studios for high resolution special effects sequences.
Read more about VistaVision: History, Special Effects Usage, Technical Specifications