Christopher Nolan refused to use CGI for scenes in 'Oppenheimer'.
The 52-year-old director has helmed the new movie that stars Cillian Murphy as J. Robert Oppenheimer, the physicist behind the nuclear bomb, and explained how he required "the bite of real-world imagery" to portray the danger of the weapon.
Speaking to Collider, Nolan said: "There are no CGI shots in this movie.
"I think computer graphics, they're very versatile, they can do all kinds of things, but they tend to feel a bit safe. That's why they're difficult to use in horror movies. Animation tends to feel a little safe for the audience."
The 'Inception' filmmaker continued: "The Trinity test, ultimately, but also these early imaginings of Oppenheimer visualising the Quantum Realm, they had to be threatening in some way.
“They had to have the bite of real-world imagery. The Trinity test, for those who were there, was the most beautiful and terrifying thing simultaneously, and that's where we were headed for this film."
Nolan also detailed the painstaking editing process that goes into his blockbusters.
He explained: "Structurally, the films tend to be fairly disciplined, and things transform over time. The approach Jen Lame, my editor, and myself take is to view the film as a whole.
"So we're watching it every week. We're putting it up, usually inviting one or two people in who don't know anything about the script to watch it with us and see it through their eyes."
Nolan added: "Every film presents unique challenges. There's a feeling of confluence at the end. But every film is different.
"Some films are improved in the edit suite through tightening and speeding things up a lot, and that's very often our process."