Production VFX supervisor Andrew Jackson gets quite ‘particular’ discussing the visual effects in Christopher Nolan’s hit biopic about J. Robert Oppenheimer, his life and work leading The Manhattan Project’s development of the world’s first nuclear bomb.
Much has been made of director Christopher Nolan stating that there is no CGI in his hit biopic, Oppenheimer, which has been taken to mean that everything was achieved practically. In truth, practical elements were digitally composited together to illustrate the mental state of theoretical physicist J. Robert Oppenheimer, who led The Manhattan Project that produced the world’s first nuclear bomb. “All the way through the script there were lines related to the thought processes he was going through in his early life with his studies and developing the ideas behind the quantum physics and subatomic particle world,” states VFX Supervisor Andrew Jackson, who won an Oscar for his work on another Nolan project, Tenet. “What Chris needed us to do was to come up with images that could illustrate those moments when he’s thinking about particular things. I was tasked with finding things that we could build, and film related to those lines in the script and could be used to illustrate those ideas.”
Rear projection was one technique Jackson utilized. “While the main cast was being filmed, we had a big projector close to the camera. We would take photographs of the set, put it through a ripple effect and project it back onto the same set exactly lining up with where the still photography was taken from. It had the appearance of making the real set move and vibrate; that was happening in real-time behind the actor while they were filming him.”
Experimenting in the Los Angeles workshop of SFX Supervisor Scott Fisher was a joy for Jackson, as his background is in practical effects. “It was like putting on an old pair of shoes,” he shared. “The workshop environment, tools and machinery have changed little over the last 10 years since I’ve been in that world. It’s different from the computer world where everything changes all of the time.” The project required a Skunk Works approach to visual effects that would have made the legendary Douglas Trumbull proud. “I always love to make and build things for all the work that we do even if its only reference or inspiration,” Jackso says. “It’s always good to have some real physical examples of the type of thing you’re trying to achieve.”
Noting the end goal was something naturalistic and cinematic, Jackson reveals, “The explosions themselves had quite a bit of work done in layering up multiple elements to get them to the scale of the real explosions. We filmed detailed sections and used them so that the overall effect was at the right scale of the actual nuclear test. We referenced archival footage and it was a close match.” High explosives and liquid fuel were key components. “The explosive work was filmed [on IMAX] in New Mexico 50 miles south of where the actual test took place, which was a good match for the environment. They were huge explosions that were closer to the camera than the real thing so the perspective scale matched.”
The shooting took advantage of a special lens produced by Dan Sasaki at Panavision in partnership with cinematographer Hoyte van Hoytema. “That long, narrow probe lens was useful shooting some of the miniature and subatomic particles work we were doing,” remarks Jackson. “IMAX cameras are big, and having a long narrow lens, enabled us to get in amongst smaller events and capture that immersive feeling inside of a smaller world.” A variety of practical techniques were utilized to create the desired micro photography. “We had spinning beads, magnets, ball bearings, and cloud tanks, in fact all of those old school effects techniques were used,” he continues. “We had big water tanks that were round and swirled around. We used metal flakes in the water, with the probe lens working through a hole inside the tank with a rubber membrane so it could move in and out. Those were some of the starfield or galaxy effects; they became backgrounds for a whole lot of other effects that we used. We were using a material called thermite, which is an amazing combination of powder and iron oxide. When you burn thermite at 20000 C it turns into molten iron. We filmed a lot of that at various different levels for quite large-scale things and at that temperature it’s incredibly bright so it looks like a little star.”
Adding to the film’s creative challenges was that there is no real photo reference for the subatomic world. “It would almost be an impossible thing anyway because the electrons are spinning billions of revolutions per minute and they’re so minute relative to the scale of the orbit they take that it doesn’t lend itself well to photography,” Jackson states. “There would be nothing to see because the particles are so tiny. Also, we didn’t want it to be too diagrammatic like an infographic. We were trying to understand what was happening in that world and then come up with artistic representations of those ideas and hopefully things that will look good on camera that were feasible. We didn’t want to get into building incredibly complex devices to illustrate these ideas. They’re all simple things that could be done quickly.”
Jackson adds, “We were constantly striving for ideas that incorporated both particles and waves because there was a lot of thought around that idea in the subatomic world, especially in the quantum world, that these things exist in two states. One of the first things that I did was depicting particles spinning in a loop and trying to vary the length of the radius of the arc. But that didn’t work well at all. It didn’t read on camera so we ended up making them describe a vertical wave as they made their arc. That worked much better. We built rigs that had multiple spinning arcs centered around the same center. That created an exciting look, and we used that quite a lot in the film.”
These experiments ended up as the equivalent of storyboards. “That was the process of working out what the visuals were going to be for us,” states Jackson. “There would have been no point to try to storyboard an experiment we hadn’t done yet because we didn’t know what was going to come out of it.”
In an unusual move, the visual effect unit had its own film unit. “David Drzewiecki was our DP and he worked closely with me and Hoyte on the whole show,” Jackson says. “As we were filming elements and shots, we would be looking at the results of our work in dailies with Chris and Hoyte. We would discuss any alterations or changes that we wanted to make based on the early tests.” Post-production lasted 3-4 months with the entire movie being completed within a year. “For Chris, the ultimate visual effect is not to have to scan the film and not do any work on it in post. He wants to have shots that can be cut into the film. I always keep that in mind when I’m shooting stuff to try to frame it in a way that it can work without any work at all. It’s great when that happens.”
Compositing was pivotal in seamlessly layering the various photographical elements. “The visual effects work on this show was compositing,” Jackson describes. “Chris came out early on and said, ‘There’s no CG.’ To clarify that meaning that the components we used were all photographic elements and there were no computer-generated elements going into the compositing work. But there were visual effects in that a lot of those shots were a complex layering of multiple elements.”
All told, Oppenheimer included approximately 200 visual effects shots, “but many of those were cut straight into the film,” explains Jackson. “We shot a lot of material that didn’t need additional work in post. There are probably 200 shots and half of those were worked on in post-production. Some of them were worked on extensively and rebuilt as multiple layers where others were a simple addition of a couple of different layers.”
DNEG was the sole visual effects vendor, having collaborated with Nolan since Batman Begins. According to Jackson, “It works well for Chris as he knows DNEG and DNEG knows how he likes to work and the process with film and the rest of the technical background. It’s a straightforward process.” He goes on to share this experience as production visual supervisor on Dunkirk and Tenet came in handy for Jackson. “After doing three films now I understand clearly the things that are important to him and the way he likes to work. He probably trusts me in the way that I approach things and the work I’ve done for him in the past has been successful and works well for him. I appreciate the freedom Chris gives me to experiment and he is open to people bringing new ideas and different ways of solving the challenges of each film. Once we have some ideas and have done some tests, he’s collaborative and we work together in refining those ideas and turning them into the thing that ultimately ends up in the film.”
Trevor Hogg is a freelance video editor and writer best known for composing in-depth filmmaker and movie profiles for VFX Voice, Animation Magazine, and British Cinematographer.
