According to John DesJardin, there are over 1,100 CG shots in "Watchmen," created by four visual effects houses. While the Owl Ship was a practical set, its flying version was a CG invention, "a mixture of a spinner from 'Blade Runner' and the Millennium Falcon," he describes. MPC created that and the craft's light beams, and also worked on fire and riot scenes on the streets of New York.
For the opening title sequence that provides "Watchmen's" historical context, CIS recreated Times Square in the 1940s, as well as the JFK assassination, incorporating footage shot on a Vancouver parking lot repainted and dressed as a road.
Except for a 20-foot x 20-foot bit of ground shot on a green screen stage, the surface of Mars is completely CG, as is the glass palace that emerges from it. "Some of these pieces were 20 feet tall and five feet thick, so it was an enormous amount of glass," says Peter Travers. "And it had to work with everything else going on in the scene, particularly when it was coming out of the ground, with all the debris and rocks and dust coming up. The rendering times on that were tremendous."
Imageworks also created Ozymandias' pet Bubastis, combining elements of a lion, a tiger and a lynx, and digitally destroyed New York City. "We started with models that we had before, from movies like 'Spider-Man' but then we had to build all the interiors, the internal structures that had to interact," notes Travers.
His team was also responsible for creating the Vietnam flashback. On set, a small rice paddy was built against a blue screen (used instead of green screen when there are green elements in the scene) and supplemented by a few miniatures for trees and fire.
CGI effects and set extensions, though expensive, prove to be cost-effective, says producer Deborah Snyder. "It allows us to build less physically. It helps our budget and allows for more spectacle."