West Side Story

What is 70mm?

We’re glad you asked! The ancestor of IMAX, 70mm refers to a high-resolution film stock twice the width of ordinary 35mm film. 65mm of the 70mm area is allocated for picture recording and the remaining 5mm for the high-fidelity, six-track magnetic soundtrack (replaced, on newer 70mm prints, by digital sound encoding). While experiments with large-format motion-picture stocks date back to the late 19th century, Hollywood first became interested in the late 1920s, when Fox Film Corporation (the forerunner of 20th Century Fox) introduced a short-lived 70mm film process known as “Grandeur,” used most notably by Raoul Walsh for his 1930 western The Big Trail. (A 35mm version of the film was shot simultaneously.) But the Great Depression and strong resistance from theater owners still in the process of upgrading to sound doomed Grandeur from the start, and it would be another 25 years decades before 70mm returned with a vengeance.

Beginning with Oklahoma! in 1955, a variety of new 70mm processes began to proliferate, including producer Mike Todd’s signature Todd-AO format (which employed a frame rate of 30 frames per second instead of the standard 24) and Ultra Panavision (which used a combination of 70mm stock and anamorphic lenses to create an extra wide 2.76:1 aspect ratio, seen in our series in Khartoum and It’s a Mad Mad Mad Mad World). In addition to those screening here, other films originally shot in 70mm include Around the World in 80 Days, Ben-Hur, Cleopatra, Lawrence of Arabia and Patton. The expense of making prints and equipping theaters with proper projection equipment kept 70mm restricted to premiere or “roadshow” engagements in major cities—with 35mm “reduction” prints created for general release—but the format remained in active use for big-budget studio prestige pictures throughout the 1960s, and was used for several decades after that to create “blowup” prints of 35mm movies for special engagements.

Championed by such filmmakers as Paul Thomas Anderson, Brad Bird, Christopher Nolan and Martin Scorsese, the technology lives on in the form of IMAX (which uses 70mm film stock run horizontally through a specially designed camera) and in occasional films shot in traditional 70mm, including this year’s The Master and Samsara.