Cameron and actor Zoe Saldana (who portrays fierce Na'vi princess Neytiri) spoke to an audience of actors in January after a SAG Foundation screening of the film. They revealed how nothing the actors did in front of the camera was exaggerated or changed by the motion capture and how the technology in "Avatar" was used in conjunction with the actors' performances, not to replace them. The experience was, in Saldana's words, like "playing in the world's most amazing sandbox."
On why it took so long to bring 'Avatar' to the screen:
James Cameron: Basically, it wasn't possible [in 1995]. They had motion capture, but there wasn't really anything for facial performance. They were basically trying to capture facial performance the same way you capture body performance. It works very well for bodies because it only takes a marker in a couple places to define where the forearm is. But it takes hundreds of markers on the face. It's pretty close to true that there are as many muscles in the face as there are in the whole rest of the body. So to try to use the same system for face and body doesn't work.
What we did that was new on "Avatar" was we uncoupled that; we did it separately. We created a separate system with a facial camera that doesn't just read the face, it gets the eyes very accurately and even the kind of internal workings of the mouth. Which, you're kind of not aware of when you're watching the movie, but every time the actors open their mouth, you see into their mouth. It's kind of obvious when you think about it, but the interaction of the tongue and teeth and the lips, that's how we form speech. And if it's not done right, it just looks wrong. So we're essentially shooting a close up of the actor 100 percent of the time.
Also, we just felt the general state of the art of CG needed to come up to a level of photo reality a little farther before we started. So we waited until 2005.
On how it feels to not have your face shown onscreen:
Zoe Saldana: I do believe that as human beings we are prone to vanity, especially actors. But I didn't want to become an actress because I wanted people to know my face. I wanted people to know my work. And I will say that when I see [Neytiri], it's me. I played her since 2006, and it was the hardest person to break up with. I never went to work so happy, wondering what I was going to do—I would be falling off a horse, on wires one day, practicing a new dialogue, hissing. I was doing cartwheels on my way to work. As actors, it's very hard to not feel like a puppet sometimes. I never felt like that here. And I understand how actors get addicted to working with amazing directors. It's not because they can make an amazing shot or tell an amazing story; it's the respect and acknowledgement they have for the presence of an actor.
Cameron: It's very easy, actually, to be an actor's director and work with performance capture because you're not distracted by lighting or how fast the dolly should be moving or what lens you need or how quickly you're losing sun. There are a hundred thousand details to distract you from the process of working with the actor. But in performance capture, it's all done later, so you have none of that.
I went into it with a little trepidation because I thought, "They're going to hate having this camera stuck on their head." It turns out it was distracting for the first couple hours, but soon they started loving it and having fun. We were doing the work that one would do in front of the lens in terms of creating a truthful moment as the narrative required it. I think you see Zoe's heart in this movie. Even if you never see her physically, you see everything she's feeling.
On using the technology to capture the performance:
Cameron: If you don't get it perfect on the day and you walk away without that performance, you're putting it in the hands of the animators to create something after the fact. And we never did that. The animators are the best animators in the world. And we needed the best to exactly translate the work. Their task was to neither embellish nor to allow any diminishing whatsoever. And I think that was a very rigorous discipline for them, and I think they succeeded.
The beauty of it was that the look of the character didn't change in the final CG. So we could actually do something quite slick; we could have a stunt double jump off a 20-foot tower and then do a motion stitch to Zoe standing up and spinning around toward the camera. It converted in mid-move from stunt performer to the actor and yet was seamless. In fact, we had to decondition the stunt performers to not hide from the camera because they're so used to doing that.
Saldana: I want to point out that this is a technology that can be extremely liberating and at the same time very nerve-racking. But it only works if you're working with an amazing director who will honor the integrity of the performance of the actors; and Jim, from the beginning, was very adamant with making us feel comfortable and always including us throughout all the different stages. We really got to understand we were going to be there. And it was going to be translated in such a way that even our pores and skin texture would be seen.
What he says to actors who see this technology as threatening to their profession:
Cameron: That's why we wanted to be here, to let the acting community more clearly understand what this technology can mean to them. I think there are concerns, but for me those are more like if somebody wants to create your likeness after you're dead—that shouldn't be happening. This is something an actor should have control of. I think you have to look at the upside of it, which is I think it's going to make a lot of jobs and it's going to give actors flexibility to do things they might not otherwise do. There are some makeup actors; they do a lot of stuff in makeup because they're good at it. There are some actors whose skin does not get affected by having rubber glued on their face, so it's known they can play aliens or witches or warlocks. But some actors have sensitive skin; they just can't do it. If you want to step outside your own physicality, you could have a 20-year-old actor play themselves at 12 and at 90 using this technique, without makeup. Think of all the great novels that take place over time that are historically done by casting three different people to play the same role. I think most actors would prefer the opportunity to play the character in as many ages as possible. Look, makeup is not going to go away. But I think we have a new form of makeup.
For example, if Clint Eastwood wanted to play Dirty Harry again, looking the way he did in 1970—well, first of all, I'd go see that movie. Second of all, he could do it this way. So I think we have to think outside the box in terms of just fantasy science-fiction films and those types of characters.