War for the Planet of the Apes hits theaters this weekend, and by most accounts, the film is a triumph (93% fresh on RottenTomatoes). I'm really excited to see it on the big screen, since it was shot in 65mm to explicitly showcase the film's landscapes and larger-than-life sets. We were on one of those sets over a year and a half ago, while the film was in mid-production. Fox invited us out to visit the shoot, on a massive outdoor prison built a few miles away from Vancouver. The Canadian winter was an ideal backdrop for this sprawling snowy set, which had its own set of railroad tracks, grungy barracks, and a towering battle-worn wall that separates soldier and simian.
The enormity and tangibility of this built-out world stands in contrast to the film's computer-generated heroes--this Planet of the Apes trilogy has anchored itself in its ability to meld the real and the digital. Actors like Andy Serkis and Steve Zahn do their best to give performances in tight-fitting performance-capture suits, but their performance is really a collaboration with the animators and special effects artists who turn mo-cap data into the characters you see on screen. On set, we sat in a roundtable interview with visual effects producer Ryan Stafford, who worked with director Matt Reeves and the effects team at Weta Digital to realize the digital characters and environments in the film. Here are some highlights from that conversation.
On compositing live and CG characters
Every time we do a shot, we do it in a variety of ways. On a traditional movie, you set up the camera, you set up your characters, you roll, get the performances you want, and you move on. Well, when we get the performances we want, we say "great, let's do that again without the actors." So we pull the actors out of the shot and we replicate the camera move as closely as possible using motion control and a lot of other tricks to get it as accurate as possible. And then we run the whole take "clean"--and if there's a human character in it, then they have to act to nothing. Sometimes we put a piece of tape up with fishing wire, and that's their eye line. And they have to re-enact the entire performance to nothing, to thin air, to a piece of tape.
The apes proportions--their anatomy--are different from humans. It's very close. We've made Caesar just a few inches shorter than Andy Serkis. And the build is similar. But where his joints are are different than Andy's. His arms are much longer. His legs are shorter, his chest is more barreled. So when we put Caesar on top of Andy in the shot, there's a lot of Andy left. And we have to paint that out. Painting out things is very expensive, it's very labor intensive, it's very complex, especially when you have very dynamic camera movements. So we do it all on a clean plate in hopes that it's as dynamic as with the actors in it so we don't have to paint anything out.
We use both. It's kind of a mixed bag. Our ideal scenario is a clean plate but we have maybe a 60% success rate with that. We still have to do a lot of cleanup with actors still in the shot. That's mostly performance driven. The reality is that you're going to get a better performance from a human character when they're acting against someone else in frame. Particularly Andy, who has such a great presence, you get a much different experience than if someone's acting against thin air. In those instances, we take the clean plate, and use that information to do an overlay, try to get as much information, and steal as information as we can.