In the lead-up to his historic epic Oppenheimer, acclaimed director Christopher Nolan made a bold, widely misunderstood claim about visual effects in the film. When speaking with Collider Editor-in-Chief Steve Weintraub, Nolan stated that the finished film contained no CGI shots. Yes, a film about the history-changing Trinity Test during which an atomic bomb was detonated would apparently, according to the director, contain zero CGI shots. And from there, the world wondered in astonishment how they would achieve such a visual feat, even leading some to (very incorrectly) assume an actual atomic bomb was detonated for the film.
Nolan’s original statement, according to Oppenheimer visual effects supervisor Andrew Jackson, led many to believe incorrectly that the film contained no visual effects at all. That’s definitely untrue. They’re just not CGI-based visual effects.
“There are visual effects, but all of the shots we did were filmed or based on filmed elements. A lot of that material [Oppenheimer having visions early in the film] was filmed and cut straight into the movie. There are other ones that are simple composites of a couple of layers — one thing added over the top of a different background,” Jackson explained. “Then there were much more complex compositing effects. For the bomb, the Trinity bomb, we use multiple layers of filmed elements. Some of the effects didn’t really require any post work. They were really just cut straight into the film.”
As with all Nolan projects, Oppenheimer was built through a film-focused, practical methodology, relying as little as possible on digital processing. That direction suited Jackson well as his background comes from the world of practical effects and miniatures. He is very comfortable with producing as many effects as possible “in camera,” or created strictly by using filmed elements.
Nolan’s script provided no specific direction on what would need to be recreated through visual effects, aside from the obvious Trinity Test of course. Jackson found the most challenging aspect of his work on the film was to determine what ideas within the script they would need to render visually. For example, during Oppenheimer’s (Cillian Murphy) study at Cambridge, he frequently has visions of nuclear activity, all of which were rendered using either shots cut directly into the film or composite shots using multiple filmed elements.
The entire film contains roughly 200 visual effects shots. Many of those were practical, but some were needed to remove more modern hallmarks from shooting locations. But for the climactic Trinity Test, Jackson and his team, including special effects supervisor Scott Fisher, needed to find the best practical solution for this massive undertaking.
“We knew that we were going to have to set off some pretty huge explosions and make them as big as we could possibly do it. Then, we knew we would need to use multiple layers of the material that we shot, composite them together to build bigger events and shoot them at high frame rate and slow them down even further. We knew we would need to add additional components for the ground, the shock waves. We knew what the approach would be right from the start, and it was just a case of going ahead and testing it,” Jackson recalled.
And no one was harmed in the reaction of the Trinity Test, not even a single singed eyebrow.
“The explosions were big, but they weren’t so big that it was dangerous where the camera and the actors were. They felt close enough, but I don’t think anyone ever felt threatened by proximity to the explosions.”
Oppenheimer is now available on Blu-Ray, 4K Blu-Ray, DVD, and streaming.