In a special-effects bonanza such as "Watchmen," a single effect like Dr. Manhattan's eerie blue look could easily be lost in the tumult of nuclear explosions, flying ships, Martian palaces and Antarctic lairs. But with more than 300 shots totaling about 38 minutes of screen time, the effect had to be executed to perfection.
Since digitally adding the blue glow to the superhero character played by Billy Crudup in post-production would be prohibitively expensive, John "D.J." Des Jardin, visual effects supervisor on the Warner Bros. film, had a colleague build a glove covered in LED lights to shoot motion-capture tests. "The light from the LEDs was diffused with low heat. Once we had a glove that worked, we built a full suit."
Over at Sony Pictures Imageworks, visual effects supervisor Pete Travers was tasked with creating the Manhattan effect. Usually, motion-capture performances are done on a special stage. But the Manhattan effect had to be created on normal film sets and locations.
Black tracking marks were made on Crudup's face, with the blue LED lights serving as tracking markers across his body. Travers brought in high-definition cameras (or "witness" cameras) to focus on specific aspects of the actor. "We'd bring all the footage back to Imageworks and sync it up -- the film plate, the witness cameras, the facial performance."
The actor's every action was captured on film, including scenes in which Dr. Manhattan is 100 feet tall. "Even in those shots, we had Billy off-camera miming the performance," Travers said. "We had the witness cameras on him. Then Billy could actually see what his character was doing. That became very important."
Using the motion-capture performance as a guide, Travers' team added the computer-generated Manhattan character on top of Crudup. "There were always points where we'd think, 'Why doesn't that look right?' That's when we brought in . . . animators to match the performance in spirit."
And how did Crudup feel about having his work literally painted over?
"Pretty early on in the shoot, Billy came over to me and said, 'I was slouching in that last take. Can you take that out?' " Travers recalled. "It was a nice moment."