Christopher Nolan

Only 19 US theaters have IMAX 70mm screens to show 'Oppenheimer' as Christopher Nolan intended

While more than 20,000 people have already bought tickets for Christopher Nolan's "Oppenheimer," only 19 theaters in the U.S. have the capacity to show the movie as the director intended.

In an interview with The Associated Press, Nolan explained that the "best possible experience" of the movie is in IMAX 70mm theaters, as both the aspect ratio and the sound will be ideal.

So what difference does the size of the screen make for the viewing experience? Here's what to know about the IMAX 70mm experience.

More:Christopher Nolan made 'Oppenheimer' because he thought he'd die in a nuclear Armageddon

What's the importance of 70mm screens?

"Oppenheimer" was shot using some of the highest-resolution film cameras that exist. The film was shot entirely on large format film stock, meaning a combination of IMAX 65mm and Panavision 65mm

"The sharpness and the clarity and the depth of the image is unparalleled," Nolan said in an interview with the AP. "The headline, for me, is by shooting on IMAX 70mm film, you’re really letting the screen disappear. You're getting a feeling of 3D without the glasses. You’ve got a huge screen and you’re filling the peripheral vision of the audience. You're immersing them in the world of the film."

While it's impossible to shoot all of the movie in IMAX (as the cameras are too loud for scenes with dialogue), sequences that used the IMAX cameras will expand to fill the entire screen in 70mm theaters.

How else can you watch 'Oppenheimer'?

Cillian Murphy stars as theoretical physicist J. Robert Oppenheimer, whose work on the Manhattan Project led to the atomic bomb, in Christopher Nolan's "Oppenheimer."

If you aren't near one of the few theaters with IMAX 70mm screens, you'll still be able to enjoy the film, Nolan said.

In any IMAX theater, including IMAX digital, the sequences shot with IMAX cameras will still expand to fill the entire screen, allowing viewers to experience the full effects.

Viewing on other "premium large format" (or PLF) screens 70mm, 35mm and Dolby Cinema will be impressive for audiences.

Nolan said his team has worked for six months to digitize the original film for other formats to ensure the best experience on every screen.

Where are the best seats in movie theaters?

While seats are a personal preference, Nolan said he likes to sit in different places for different kinds of screens.

"When I'm in a theater that’s Cinemascope ratio, I like to be right near the front, middle of the third row," he said. "When I’m in a stadium, IMAX 1.43:1, then I actually like to be a little behind the center line right up at the middle. So, a little further back."

What is IMAX?

IMAX by definition refers to the firm that manufactures high-resolution lenses, film codecs, projectors, and movie theater equipment.

However, the term is often used to describe the movie format and the viewing experience specific to IMAX cameras and theaters, according to the Nashville Film Institute.

IMAX theaters have a screen the entire width of the movie theater and loudspeakers behind the screen. IMAX cameras produce high-quality images, using 70mm film.

Additionally, IMAX theaters have a large circular dome and a flat screen, giving viewers a more life-like experience and the same view of the screen from any seat.

IMAX film resolution is almost 10 times more than a 35mm projector and each frame has some 18,000 pixels of resolution versus a home HD screen that has 1,920 pixels.