Issue link: http://digital.copcomm.com/i/40055
alike in their underlying facial structure, the way their muscles and tissues work,we were able to then translate the actor's performance into the chimp's performance." POST: How many digital chimps did you create? LETTERI: "There were four lead chimps, probably about another dozen secondary ones, and from those we have scenes where there are hundreds.We reused those 12 or so and just varied them slightly to populate the town." POST: Did you use Massive software? LETTERI: "Yes,we did." POST: What did you use for compositing, and can you talk about that process? LETTERI: "We used Nuke.We had a number of techniques that we've developed, especially through the course of Avatar. Even though we didn't do this as a 3D stereo- scopic film (it was shot 35mm), we did use the 3D compositing pipeline that we devel- oped on Avatar, and that really is helpful be- cause you now have control of every pixel in depth. You aren't just breaking things down in planes or elements like we used to in the early days, so it really makes it a lot more flexible to figure out how you need to combine elements and work with them after the fact. "We also used Nuke's 3D capabilities... to projection map backgrounds and skies and everything,so we could get the backgrounds working pretty quickly. There are a lot of things you have to do when dealing with paint out — there is a lot of cut and paste and re-projection and things like that, and Nuke, because it has that built-in 3D engine, is really helpful for that." POST: So no 2D-to-3D conversion? LETTERI: "No stereo at all on this one. We thought we couldn't shoot it stereo; we just didn't have the time because of the tight release schedule. Everyone wanted all the work to really go into the characters rather than worrying about stereo. So Fox sort of took that off the table early on. Fox knows, because we've done this with Avatar, if you are not shooting in stereo, you really don't want to convert. It's better to do it right or not do it at all, but commit one way of the other." POST: Backtracking a bit, what was the previs process like? LETTERI: "We didn't do too much of the previs on this film because director Ru- pert Wyatt had a previs team working with him directly, so a lot of that was to flesh out story and script ideas and blocking for the stage and things like that. "What we did was a little bit more ani- mation driven, where we were just working out real performance beats and figuring out what the motions of the chimps would be. Because as much as you have actors per- forming this with their arm extensions and trying to be quadrapedel and everything, you still have to translate that to realistic chimp motions. "You have to discover when an actor does something, what the analogous motion is because you kind of understand what they are after — but because the knees and an- kles and everything bend in different ways, you can't just take all the capture data liter- ally. At some point you have to blend into what the chimp has to do to get the right foot contact and right joint angles. So we spent a lot of time in the early days doing character studies to figure out that motion and how we would put that together." POST: Did you rely on videos or live chimps? LETTERI:"We saw live chimps because we work out of Wellington and the zoo there has a great population of them.They allowed us to spend a lot of time there photographing and filming.Then the anima- tors had to go in and look at that and any other references, and start tracking and matching the animation, and learning about how chimps move." POST: And making them believable? LETTERI: "Yes, the biggest challenge is really just building the believability of the characters. Just looking for those moments when you can really get what the character is thinking, and they become part of the story. Every scene just requires one of those keystone moments where you figure out this is what's working and then all the other shots can hang around that and come together." POST: How was it working with the direc- tor Rupert Wyatt? LETTERI: "We treated it very much like a live-action film.We had Andy Serkis and the other actors in the set, and be- cause they were the same size as the chimps,we decided early on to just shoot it like it was live action. That way you get everything you want. If you want a close-up, you have Andy turn to camera or if he's run- ning and the cameraman needs to track with him, then use that performance be- cause you can cut with it… everyone has a guide and it just works. "So, even though we were capturing all the performance live,we didn't overlay Cae- sar onto the camera or anything. Not only was it not necessary, it actually would have gotten in the way. Andy's performance was the one you wanted, not the plastic Caesar that you could do in realtime, so we just treated it like live action and kept that as our model all the way through." www.postmagazine.com August 2011 • Post 15 Weta created four lead chimps and a dozen secondary ones — from these they populated the entire film.