Here’s how production visual effects supervisor Adrian de Wet and on set visual effects supervisor Sean Stranks combined on The Hunger Games: The Ballad of Songbirds & Snakes. A new excerpt from befores & afters magazine.
As Francis Lawrence’s The Hunger Games: The Ballad of Songbirds & Snakes began pre-production for a 2023 release, the director’s frequent visual effects supervisor collaborator, Adrian de Wet, was still in the final stages of delivery on Slumberland (also directed by Lawrence) so he brought in Sean Stranks as on set visual effects supervisor.
“There was going to be a bit of an overlap between films,” de Wet told befores & afters. “I knew it was going to be tricky to juggle both projects. But I’ve known Sean Stranks for years. We go way back to ESC, and I worked with him quite a lot at DNEG. He’s very, very experienced, very capable, great eye, super creative. Most importantly, he knew what had to be done on set. He can speak to a crew knowledgeably about how to do certain things and set it all up correctly.”
This on set role involved more than just being present during the 85 days of filming. Stranks also attended set recces at shooting locations in Poland and Germany, and helped ‘prep’ the VFX side of the film over two months, all while staying in constant contact with de Wet and visual effects producer Eve Fizzinoglia.
“I was going to be there for Poland, for the scenes in the arena, but nothing else,” says de Wet. “Everything else I delegated to Sean. He came up with a lot of the methodology for shooting a lot of these things. I was having daily conversations with him to just make sure that I was kept abreast of everything, but really I delegated all that to him and he did a great job.”
In the arena
Earlier, the VFX production team had engaged Halon Entertainment to previs two of the film’s biggest sequences, involving the bombing of the arena and the later snake attack there. That previs helped inform several departments’ approach to making those sequences, including, of course, VFX.
“We knew it was going to be filmed at the Centennial Hall in Wrocław, in south Poland,” notes de Wet. “It’s a beautiful 1912 art deco arena. Production designer Uli Hanisch had gone there and done some very basic geometry scans. That gave us a rough model for our previs. We were going to put a huge hole in the ceiling that was going to be all digital from the bombing, and that we’d have to add damage everywhere.”
Stranks himself was part of several recces to the Centennial Hall, and was quite taken with its massive size. “The great thing about that location was that it had all those shutters in the windows that actually opened the way they do in the film. In the film, it goes from super dark, and then they all open and it’s a big reveal. Meanwhile, the art department made this entire floor for it, and they made sections of walls that went around. And then for visual effects, we worked out what would go beyond that, and how the arena would look post-bombing, including with the big hole in the roof, and debris.”
Indeed, debris around the arena would prove to be a particular challenge. The art department had built debris pieces for use on set, but to get several dynamic sweeping shots in the area–in addition to a number of camera drones flown inside the Hall–an electric tricycle was used as a camera car, and required clear paths to drive on. “It meant we had to do some work to position the debris back onto those paths in VFX,” advises Stranaks. “We LiDAR’d and referenced as much of the real floor and dust and debris as possible to be able to re-create it in CG and put it back.”
That LiDAR work was overseen by lead data wrangler Callum Ruddleston from We Shoot Lasers. “It takes such a long time to do that really accurately and properly that we had to schedule it,” says de Wet. “Callum came in two days at the weekend to do a really fine scan of the arena with all the rubble and all the practical destruction. We then sent that to VFX studio Important Looking Pirates which used that as the basis for building the asset, and shared it with other vendors.”
The snakes that are unleashed in the arena are fully digital. However, discussions did take place about building practical versions for reference during filming. One snake was made out of rubber but eventually not used. “There were also some pretty good ideas of attaching little silicone snake heads attached to people’s clothes,” notes de Wet. “But with that, you don’t really want to lock yourself into these interactions. So we said, ‘Let’s just shoot it and we’ll replace it and we’ll make sure we get all the data.’”
“It really came down to the imagination of the director and the actors about what was happening with snakes,” adds Stranks. “They weren’t big snakes–not big boa constrictors or anacondas–they were little snakes. So the actors could keep some of their natural movements and play what they thought that might feel like, having tens of thousands of them crawling all over their bodies.”
Ghost VFX handled the CG snakes in the arena, while also delivering complex cloth simulations to make the snake interaction with the costumes as close and convincing as possible. Scans of the actors in their costumes helped inform that work. “Lucy Gray’s (Rachel Zegler) dress was particularly challenging, being slightly transparent and with its frilly lines and cuffs,” observes Stranks. “Initially we were trying to decide how much clothing did we want to keep? Should we have green sleeves or green pants, for instance? But then we decided to always just keep their great costumes. From an on-set perspective, it was then about gathering as much data as we could to help with body tracking and rotoscoping. We had some witness cams there, but the team from Ghost did such a great job on the tracking and then the snakes and the clothing.”
Communicating VFX shots
Visualizing shots or scenes was one area Stranks also worked on, often while on set. Discussed further below is an effort he made to provide a previs-level vis of the train arrival at District 12, but Stranks used other visualization methods, too, including crafting paintovers on footage or reference images while going through scenes with de Wet.
“I would take the frame from the film and say, ‘Okay, this is what we talked about on the day. We’re going to get rid of that structure, we’re going to add this, we’ll change that, etc etc.’ It was a matter of grabbing a frame from DIT, even if it was a screengrab, doing a paintover, and then I’d have it there as a point of discussion.”
That kind of work was typically done on an iPad running ProCreate or Photoshop. Stranks also made use of an app called Scriptation that allowed him to annotate and break down scripts. “You can bring in the latest version of the script, you can see the changes from the previous version to the new one. You can very quickly annotate over it, add images to it and add notes to it. That gives you a go-to in the script for what’s been discussed rather than just looking at a spreadsheet on set. Sometimes, a spreadsheet can only tell you so much.”
On his laptop for on set, Stranks ran Blender and DaVinci Resolve for mocking up shot ideas, as well. “If I don’t have anything to use for a paintover, I can usually just create it in Blender quickly with some very simple shapes, then bang out a very quick render, and then do a paintover on that.”
Find out more in the full article in print.
