For Wells, performance capture is the best of both worlds. Courtesy of ImageMovers Digital.

As the great-grandson of H.G. Wells, and a 25-year veteran of animation and live-action (including The Time Machine remake, The Prince of Egypt and Balto), Simon Wells was perfect director for Mars Needs Moms, adapted from the Berkeley Breathed children's book, and the final feature made by Robert Zemeckis' ImageMovers Digital.

Bill Desowitz: What do you think of performance capture?

Simon Wells: I'm absolutely in love with the process because it has all the best parts of both. I get the joy of working with actors live in the moment -- the chemistry and the immediacy of the performance. And you have to work very, very hard in animation to get that liveliness to happen. You can do it, but it's pushing a rock up hill; and it comes naturally when you have people like Seth Green and Dan Fogler making it happen. So this was great because you get all the fun of working with the actors and doing the scenes without having to do all the starting and stopping and coverage. So you get the perfect take and all of that technical cinema stuff you do later. And it's kind of fun to bring the animation sensibility and knowledge of things like facial performance to work with the animators in bringing those performances to life in the 3D figures. So, for me, it was really nice to blend this weird collection of skill sets that I'd accumulated from a whole lot of different sort of movies.

From a philosophical point of view, there's no point in doing performance capture for films that certainly should be live-action, and there are animated films like Madagascar that certainly shouldn't be performance capture. So I think there's an area in the middle that's the perfect meet for performance capture and it's neither animated nor live action. One of the things we deliberately did with the Martians in this film was so they couldn't be people in suits. And actually you could push it much further with people that aren't human but being driven by the human performances.

If it's Mars, it must be Wellsian.

SW: When we were writing, we'd hung out on set because Bob was shooting A Christmas Carol, and I was very keen how you direct motion capture. I had visited Bob on the set of Polar Express but that was still very early days. So, part of it was just an educational thing: How do you run the day? How does it work? But when it came to actually shooting, I found it surprisingly natural. I don't mean that in the arrogant -- Oh, I know how to do that! It really fit in a comfortable way I felt working with the actors. I knew in the back of my head how it was going to work with the cinematography later. And I knew what I would be able to do through the animation process. I didn't have to worry about the actors exactly hitting their marks, because I could always shift the figures later to get the compositions right.

BD: Did you do it the same way as Zemeckis, doing performance first and then concentrating on the environments?