Even though The Odyssey is the first movie to be shot exclusively on IMAX cameras, the epic still had to adhere to the company's runtime limitations, despite how much director Christopher Nolan tried to work around the constraints.

"It's still three hours on the film prints, said Nolan in an interview with Letterboxd. The Odyssey's runtime is 2 hours and 52 minutes, but after the director had previously pushed IMAX to its limits by making Oppehnimer exactly three hours long, he planned to make his ancient Greek epic run even longer. However, Nolan's IMAX mentor of 20 years, David Keighley, set him straight.

"He actually dragged me into the booth at some audience film to show me the final limitation of this 3-hour limit on the film prints because over the years I challenged him to enlarge the platters or come up with a clip system to hold the film end when it got a bit bigger than the platter, that kind of thing," explained Nolan. "But there's a particular arm that would require an entire rebuild of the projection system to get beyond that. So I finally said to him, 'Yeah, okay. I'll stay under 3 hours.'"

Keighley was IMAX's first chief quality officer and helped put over 500 movies on the biggest screens in the world, including some of the best Christopher Nolan movies, such as The Dark Knight, Dunkirk, and Oppenheimer. Keighley sadly passed away last year, right after finishing work on The Odyssey. The newest IMAX camera, known as the Keighley, is named after the late great cinematic pioneer.

The reason why IMAX movies have to be under three hours is that the platter that physically holds the IMAX film print can only fit so many reels, and so longer films would require a whole new system. To fit larger equipment in all IMAX cinemas all over the world would be extremely costly and time-consuming.

There is also the audience to consider. Longer movies mean fewer screenings per day and fewer moviegoers seeing the film. There are only around 1800 IMAX cinemas around the world, and just 30 of them have the true 70mm IMAX ratio. With how fast The Odyssey 70mm tickets sold out, IMAX will struggle to fit fans in as it is.

The Odyssey is in theaters on July 17. For more, check out our The Odyssey beginner's guide, and keep up to date with all the movie release dates coming this year.