Playing Iron Man for a day

On Tuesday, the DVD version of the mega-hit film Iron Man will be released, and to celebrate, the visual effects superstars at Industrial Light & Magic decided to show off just a little bit more magic behind the movie.

Back in April, ILM invited me and a couple of my colleagues to their fantastic facilities here for a look at the technology behind the famous suit used in Iron Man. Recently, they invited us back to see how the seamless animation in some of the film's scenes--such as one famous shot involving the throwing of an Audi--was produced.

In particular, they wanted to give us the inside scoop on the motion-capture technology used to create a number of the film's scenes, a technology that is increasingly being used today that allows directors to see, in real time, while the actors are acting, what animated sequences will look like.

That's why we--myself, CNET reporter Kara Tsuboi, and a cameraman--spent several hours on an ILM image capture stage last week: So that Tsuboi could don a motion-capture suit and we could all see how footage of her would translate instantly into an animated Iron Man scene.

The idea is that George Lucas--who owns the effects studio--wants to give filmmakers advanced technological tools that provide them with flexibility and efficiency. And so he staffs ILM with the kinds of people who can make that happen.

"We understand the entire process," said ILM digital supervisor Michael Sanders, "from writing code to animating creatures to even shooting live elements. So we know each layer in the process. We understand the vision of the key creatives and understand" what the actors are going to do.

The technology used at ILM--and elsewhere, as well--allows directors to mix real filmmaking and virtual spaces, but with full camera control, depth of field, tracking, and panning. The upshot? A filmmaker can have an entire digital set created, then have an actor perform on the image capture stage wearing the motion-capture suit, and see, as the filming is happening, how the actor's character looks superimposed on the digital background.

And that means that a director--using a special wireless device that lets him or her see the entire mixed-media image in real time--can move around on the stage, looking for the angles he or she wants and creating new compositional choices on the fly.