This is How IMAX Projects its Gigantic 70mm Film
IMAX film screenings are special experiences. Not many theaters play the actual IMAX celluloid, and that is in large part because of the insane logistics involved with projecting the film.
YouTuber Adam Savage recently poked around IMAX’s Los Angeles headquarters, giving a behind-the-scenes tour. IMAX is 15-perforation, 70mm film — but 5mm of that is dedicated to audio, so the picture size is 65mm. Nevertheless, the physical image is almost 10 times the size of standard 35mm film. It has to run horizontally through the projector.
This enormous size means that an IMAX film that runs for one hour weighs about the same as a WWE wrestler, or 300 pounds.
Directors who love the format, like Christopher Nolan and Jordan Peele, will pop into the L.A. IMAX HQ to view dailies in the David Keighley Theater projection booth they have there (dailies are the raw clips from a shoot).
But before that can happen, the film has to be processed (IMAX says it uses FotoKem), and then the film is taken to the headquarters, where it’s placed on a massive, custom-made take-up platter.
Once the film is on the platter, it’s taken over to a floor below the projector. That means the film must be winched up 30 feet to reach the projector and then comes back down again onto the take-up reel. For 3D movies, the process is doubled. Watching Adam’s video, it’s clear why there aren’t that many IMAX theaters.
The IMAX film flies up, through the projector, and back down again at the breakneck speed of 337 feet per minute. 35mm film passes through at 90 feet per minute, for comparison.
While Adam was there, the team was loading some actual dailies for an unnamed director who was coming in shortly. They couldn’t reveal it was, but one eagle-eyed viewer spotted that it said “Charlie’s Tale” on the film roll, which was the working title for Christopher Nolan’s The Odyssey.
Nolan revealed that The Odyssey used a staggering two million feet of IMAX film during production. Kodak says that one foot of 65mm film costs roughly $1.50, so that puts the raw film price at about $3 million.
