Issue link: https://digital.copcomm.com/i/6359
D I R E C T O R ' S C H A I R 16 Post • January 2010 www.postmagazine.com The Simulcam is a live-action tracking system that allows you to look at the live world and virtual world simultaneously in the same eye- piece. So it merges the two worlds, and we had the stereoscopic Fusion cameras I'd de- veloped with Vince Pace, and the whole vir- tual camera system, and then we used the Simulcam system to combine the two." POST: The Simulcam sounds completely revolutionary. CAMERON: "It is! It's amazing. I think the performance capture stuff isn't revolutionary, only in the sense that not everyone's going to run out and make a film that way. It's going to remain a niche area. But a lot of people are making movies with more and more green- screen, instead of building big sets and going on location, and audiences accept it. "So to the extent that Robert Rodriguez and Zack Snyder are making these decon- structed films that are just foregrounds, where ever ything else is added in behind them, and they're the ones really setting the trend for where film is going, then the Simul- cam is probably the most important thing to come out of this whole project. Absolutely. Because anyone can use it, whether you're shooting in 3D or not. And you don't have to use performance capture." POST: Walk us through the whole post process. Where did you do the post? How long was it? CAMERON: "We did most of our post at the studio we built in Playa Vista, where we did all the motion capture. And if we needed something, we'd just run down to the stage and capture it. We were in the stu- dio four years to the day from the time we began testing and building up the whole pipeline of how we did the capture, how we took that motion and edited and then put it back down into the volume for me to do my cameras. "All the cameras — or what we call 'cam- eras,' which are the shots in the film — were done separately from the capture. So we did capture with the actors, but I didn't take time to do all my coverage while I was doing the capture. We uncoupled that into two separate processes." POST: So where post began and ended on this film must have been hard to pinpoint? CAMERON: "Exactly. It began before the movie. And then the editing was done twice. First, you edit the performances and take, say, Sam [Worthington, lead actor] from Take 4, Zoe Saldana (lead actress) from Take 2, and maybe the master of all the characters from Take 3. Then you go do all the camera work. And once you've done all that, you have vir tual shots that you can actually cut with, for the first time several months into the process. Ever ything before that I called 'Zen editing,' as you're editing without shots. It's like Zen archer y, shooting with- out an arrow." POST: It must have been hard for you and your editors, Steve Rivkin (Pirates of the Caribbean) and John Refoua (Ghosts of the Abyss and Dark Angel). Tell us about the edit- ing process. CAMERON: (Laughs) "They were going mad! At the star t, they had no idea how to deal with this! And they're very, very experi- enced editors. They're used to all the big, complicated visual effects, but were clueless about how to tackle this film. We all just stared at each other and said, 'How the fuck do we do this?' Then we gradually figured it out and built a methodology. And it was very challenging to tease the film out of the footage, as we ended up with a film that was too long, and we had to figure out exactly what was important to the story." POST: Where did you edit? CAMERON: "We cut on Avid and we had a cutting room in Malibu and one at Playa Vista, and we had all the media — something like 40TB — in both places, which proved to be very valuable. We had a big crash at Playa and lost three blades of the system and had to reconstitute it all from Malibu. But we could cut at either place." POST: How many visual effects shots are there and how did it break down? Isn't the whole film a visual effect? CAMERON: "Yes, there's probably less than two minutes out of the entire two and a half hours that's not a visual effect. But a good portion of that two and a half hours is conventional 2D composite stuff where you've got a greenscreen foreground and you're putting in the stuff that's out the win- dows, or it's a vehicle shot with back- grounds. And then Weta did all the CG char- acters, and anything that wasn't a CG char- acter — one of the Na'vi or avatars — we farmed out to ILM, Hydraulx and Frame- store, to take the pressure off Weta, as it was such a big job. Weta did around 2,300 shots in the end, which is enormous. Titanic was just 420! That puts it in perspective." POST: Are visual effects more expensive when you do them in stereo? CAMERON: "Yes, but it depends. If it's all CG, it's just a little more expensive to do the final renders. But most of the labor over the life of the shot is animation and color and lighting and so on, and that's all very easy to render from a second eye. So maybe it's five percent more expensive. But if it's a hybrid shot that's got live action and compositing of live action and CG elements, it gets relatively more expensive. And then if it's an all-live- action shot, then it's cheap again. So there's this Bell curve of expense." POST: What was that the most difficult vi- sual effects shot to pull off? CAMERON: "It was a class of shots, rather than any individual one. It was any- thing with Zoe's character or Sam's charac- ter in his avatar form, and making them real. Once we'd cracked that, it all went pretty smoothly. But toward the end, we began to find these shots that sort of defied our abil- ity to make them look real, and they were According to Cameron, all but about two and a half minutes of the film features some sort of 'visual effect. continued on page 43