Motion-capture gives filmmakers new tool

Imagine you're a Hollywood director. You want a certain actor to be your action hero, but the part requires him to look decades younger and pounds thinner.

It can be done through the magic of motion-capture technology. That process allowed "Beowulf" director Robert Zemeckis to cast Ray Winstone as Beowulf, a character who is taller, younger and more muscular on screen than the actor is in real life.

Motion-capture is the latest advancement in the filmmaker's quest to trick the eye. It can be used in an entire movie, such as "Beowulf" and "The Polar Express," or for one character in a live-action movie, such as Gollum in "Lord of the Rings."

Motion- or performance-capture technology records an actor's movements and applies them to a different, digital character, said Jerome Chen, senior visual effects supervisor on "Beowulf."

"All this technology is an artistic tool," said Chen, who is part of Sony Pictures Imageworks, a digital-production studio based in Culver City, Calif., which used its Imagemotion performance-capture system the movie.

Chen was in charge of visual effects on Zemeckis' "The Polar Express," one of the first movies to be shot entirely in motion capture.

"Beowulf," adapted from an ancient epic poem, tells the story of a great warrior, Beowulf, who battles the monster Grendel, Grendel's mother and a dragon. The movie, in theaters, also stars Anthony Hopkins and John Malkovich.

Zemeckis could have filmed "Beowulf" using live action mixed with a computer-generated Grendel and dragon. Motion capture is less distracting than a purely computer-generated monster surrounded by live action, because it creates a world in which everything has the same look, Chen said.

Computer-generated images are sculpted digitally and do not use information collected from a live actor.

But motion capture has been used to create one character in a live-action film. Andy Serkis gave a motion-capture performance as Gollum in the "Lord of the Rings" movie trilogy, and as the giant ape in "King Kong."

The technique was used to animate the dancing penguins in the movie "Happy Feet." Tap dancer and choreographer Savion Glover performed the penguin Mumbles' solo dances, said Deron Albright, associate professor of film and video at St. Joseph's University in Philadelphia.

And in the case of "Beowulf," sculptors applied Winstone's nose, lips and eyes as they appeared when he was younger to Beowulf. The warrior's cheekbones were an artist's conception.

The idea was pushed further with Crispin Glover's portrayal of Grendel, a skeletal, misshapen creature that communicates in grunts and screams. Very little of Glover's appearance was used to create the monster.

Animators didn't mess with the objet d'art that is Angelina Jolie, who plays a seductive witch who appears naked. To emphasize her evil otherworldliness as Grendel's mother, they gave her a ponytail that becomes a reptilian tail and claws.

Back in 2004, "Polar Express" was derided for its cast of dead-eyed children, but "Beowulf" is getting a better reception. It earned $28.1 million at the box office during its first weekend.

A good story can be told in live-action, computer-generated images or motion capture, or any combination of them, Albright said.

"Ultimately," he said, "it's about the story."