Lighting pipeline speeds up effects work
“The Smurfs” may seem like an easy assignment for its visual effects team compared with, say, “Transformers 3.” The little critters themselves are very cartoony, and appear to lack the complexity of shape-shifting robots.But visual effects challenges, and the innovative solutions they spawn, pop up in unexpected places. In the case of “The Smurfs,” the vfx artists at Sony Imageworks had to develop a lighting pipeline that not only helped deliver the Smurfs in just the right shade of blue, but will improve — and speed up — the vfx work on at least two 2012 Imageworks tentpoles: “Men in Black III” and “The Amazing Spider-Man.” Faced with the challenge of making the Smurfs appear as though they were living beings inside a real world but never letting them lose their Smurf-like qualities, the film’s vfx crew found innovative ways to use equipment, notably a Spheron HDRI camera and a Trimble laser scanner. The two were combined in a new way to capture lighting and depth information on the live-action set, and that information was used later by the digital artists who had to put the Smurfs into the scene. The gear captured so much information about the live-action lighting that there was little of the usual guesswork when vfx artists had match it. Digital effects supervisor Daniel Kramer says with this approach, the lighting department could light a scene pretty much at the same time the animation department was working on the characters, instead of having to wait — impatiently — for animation to turn the shot over to them. This lighting pipeline, which was also used on “Green Lantern,” stands to speed up Imageworks’ output. Says vfx supervisor Rich Hoover: “The more you can use tools like these to gather this kind of lighting information, the more time you have to explore ways to really get the performance from a character you need for the movie to work the best it can.” The Smurfs themselves had to be handled very carefully, as their brilliant blue skin doesn’t easily fit into realistic environments. “One of the things that indicates that Smurfs are small is the translucency of their skin,” Kramer says. “So there’s going to be a color underneath their skin, just like we have the color of our blood mixing with our skin tone.” And it turns out that Smurfs have red blood. “Without that red undertone, the Smurfs didn’t integrate into the scenes at all; we let the lighting around the Smurfs influence their skin tone in the same way it would influence anyone’s skin tone in a scene,” Kramer says.