How Much Of Oppenheimer Is Real vs CGI (2024)

Christopher Nolan brings the creation of the atomic bomb to life in Oppenheimer, and here is how much of the movie is real and done practically compared to using CGI. The 2023 blockbuster stars Cillian Murphy as J. Robert Oppenheimer in a story that chronicles the rise of the brilliant physicist, the creation of the atomic bomb, and the turmoil that the weapon caused. Oppenheimer represents a slightly different type of movie than audiences are used to seeing from Christopher Nolan, but his desire to do everything as big and as practical as possible still remains.

A lot has been made about how much CGI Oppenheimer uses in the lead-up to the movie's release. Christopher Nolan replicating an atomic bomb explosion in the movie and some other artistic flourishes have created curiosity about what parts of the movie were filmed for real and captured in camera as opposed to being created entirely using CGI. The director's own comments about how much VFX is included throughout Oppenheimer's 3-hour runtime have added to the confusion even. Here is a breakdown of what moments and scenes were done for real and when Oppenheimer uses CGI.

Christopher Nolan's "Zero CGI" In Oppenheimer Claim Explained

Christopher Nolan causes some misunderstandings about Oppenheimer's use of CGI when he said in an interview with Collider that the movie included "zero CGI shots." This raised plenty of questions about what the filmmaker meant, especially since it was already confirmed that visual effects studio DNEG was working exclusively on the movie. It marked the eighth collaboration between Christopher Nolan and DNEG. That is why his "zero CGI" claim created some controversy, as it appeared as though Nolan was downplaying the role the VFX team played in creating Oppenheimer. The backlash to the quote was a matter of misunderstanding what Nolan meant.

The director was not attempting to claim that there was no CGI in Oppenheimer at all. He was instead stating that there are no shots in the movie that were entirely created using visual effects. Nolan and DNEG still worked together on various parts of the movie to add CGI to what was filmed practically. This was all done intentionally by Nolan and was part of the plan from early on during the movie's conception. The filmmaker has long had a preference for doing everything in his movies for real instead of relying on CGI, as he has a firm belief that audiences will always feel the difference.

Oppenheimer's Atomic Bomb Explosion Was Done Practically

One of the most impressive accomplishments Christopher Nolan's no CGI mindset gave Oppenheimer was a practical atomic bomb explosion. The story of J. Robert Oppenheimer's life heavily revolves around the creation of the first atomic bomb as part of the Manhattan Project. This takes up a great deal of the movie's story as Oppenheimer and other scientists attempt to build the gadget at the Los Alamos facility. The entirety of Oppenheimer builds to the first atomic bomb test, and Nolan makes sure that it is a showstopping part of the movie by how he pulls it off.

Knowing that the entire movie hinged on the moment, the decision was made to do Oppenheimer's atomic bomb explosion with no CGI. While Christopher Nolan has gone to rather great lengths to pull off practical moments before (such as blowing up actual planes), even he could not use an actual nuclear bomb for the movie. This meant working with visual effects supervisor Andrew Jackson, production designer Ruth De Jong, and special effects supervisor Scott Fisher to create a working device that would replicate the look and explosiveness of the actual atomic bomb. Every part of the explosion in Oppenheimer is real and not done with CGI.

What Oppenheimer Scenes Required CGI

The credited work of DNEG and many visual effects artists means that there are various parts of Oppenheimer where CGI is used. These moments likely include the increased shaking of the background in certain moments where J. Robert Oppenheimer feels overwhelmed, such as during his security clearance hearing or while speaking to everyone at Los Alamos after the atomic bombs were used in Japan. It is also plausible that some of how the movie visualizes his fears of the atomic bomb were done using VFX. There are moments when maps begin to look as though nuclear bombs are firing and detonating that do not appear to be completely practical.

It is unclear how much of J. Robert Oppenheimer's visualization of science was done for real instead of using CGI. The imagery that resembles space, explosions, and much more was partially accomplished using practical methods. Nolan confirmed to EW that Andrew Jackson experimented with different ways they could do these without using CGI. However, he does not confirm that all examples of these scenes were done practically. It is possible that they were, but some of the others and how they blend with the real world could be further examples of how Oppenheimer uses CGI.

Sources: Collider, EW