For a comedy piece, different lines can be stitched together digitally to ensure the film keeps the funniest material in each take. “One guy's line may be funny, but the other guy's response isn't,” Grasmere said. “If they touch each other during the shot, we may have to reconstruct an entire hand or arm. Or we'll repaint the background of a shot, merge two sides from two other moments, or superimpose something in the foreground to join two different performances. “There are a million ways to make it work.”
Many invisible effects are concentrated on faces. Performers can do body double replacements, whether for nude scenes or dangerous stunts. Most commonly, extensive cosmetic work is performed on actors: removing wrinkles, smoothing blemishes, or correcting blemishes to make actors look their best. This type of work is often called “visual makeup” or vanity VFX, and it is becoming so common that many big stars have this work written into their contracts.
“Cosmetic visual effects work is often very complex, but because we have to sign confidentiality agreements, we are rarely able to discuss or publicize that work,” said Martin Pelletier, Rodeo's visual effects supervisor. “You could do a sequel where an actor returns to a role and has gained an enormous amount of weight, and we have to come in and fix it. Or someone has a triple chin and we have to make them look nice and slim.”
“It can be a delicate issue,” Pelletier added. “We once had an actress who didn't want to look fat in a scene surrounded by a group of people. We had to lose about 80 pounds.”
One of the most common invisible effects is what is known as “reprogramming.” If a director feels that a shot or scene is too short or too long, he can speed it up or slow it down by removing or adding frames. This can create visual artifacts or a sort of unnatural distortion, or make the shot appear “jittery” and “staggered.” Visual effects artists make imperceptible adjustments “to make everything run smoothly,” Weintraub said. “It gets complicated and it's kind of subliminal.”
All of this gives filmmakers a level of control over continuity that borders on perfectionism. “Maybe there's a smudge on someone's face in one shot, or someone's hair was slightly fallen out and we have to go replace it,” Groves said. “On the one hand, it's like, who cares? Nobody will know. But at the end of the day, it's these little things that can make a movie that much better.”
