SIZE MATTERS: Lighting in 'Transformers' had to show off the robots' glossy car parts while revealing their size.
As recently as "The Empire Strikes Back" in 1980, when it was time to put a giant robot onscreen with actors, it was time to bring out the stop-motion models.
Those days are gone now, as computer-generated imagery has replaced almost all stop-motion visual effects.
But the old stop-motion models did have one advantage over their computer-generated successors. All you had to do to light them was, well, light them. They were real objects and could be lit with real lights. Digital lighting, though, was difficult, computer-intensive and didn't really look like what a d.p. would do.
Until now.
With "Transformers," "Surf's Up" and the latest wave of CGI films, digital lighting is going back to the future, as CG artists finally have the tools to light a scene the way a cinematographer does.
On "Transformers," explains vfx supervisor Scott Farrar, there were two big challenges that had to be addressed with digital lighting.
First, the eponymous robots would be made of shiny car parts, and that meant they presented the same problem cinematographers face in car commercials.
"Reflective objects reflect the world around them, so that's how you light them. You have to have a reflective environment."
So Farrar told his artists at Industrial Light & Magic to think like a d.p. might if he or she was shooting a closeup in real sunlight, perhaps blocking out the real sun and substituting his own light. "With that line of thinking, we started diving in with customized lighting. We had definite flags and nets and shiny boards, so you'd have a boxy glint coming off the robot."
The other major challenge was that the Transformers are 20 feet tall, but the wrong lighting would make them look small.
"If this guy is 20 feet tall, and steps forward or leans down to camera," says Farrar, "he's stepping out of one lighting setup and into another. Let's make it obvious that he's moving out of a left key and through a really hard and obvious shadow, then move him to a completely new light on the other side -- telling the audience I'm physically moving through three-dimensional lighting space.
"Just like a d.p., you'd have your pools of light on anything to exaggerate that feeling."
On the animated "Surf's Up," Sony Imageworks had another set of digital lighting problems. Vfx supervisor Rob Bredow explains: "Because we were going for a documentary look on the film, we wanted a very photographic language to shoot the film. We wanted it detailed enough that it would be believable that it was captured with a camera."
So the artists worked with the digital equivalent of individual lights, barn doors and filters.
"We start out with the paintings from the art department, then we set up a lighting rig to emulate those paintings. Then each of the artists who's working on individual shots in that sequence literally uses that same rig and maybe adjusts positions of lights or tweaks intensities."
Bredow says that as computers get more powerful, the lighting techniques grow with them. "Each year or two, the lighting techniques being used in an animated film are progressing, along with live-action films. We are adding those tools as we go, so each movie is getting more detailed and taking advantage of more complicated techniques."
TIP SHEET
What: Visual Effects Society Awards
When: 6 p.m. Sunday
Where: Kodak Grand Ballroom, Hollywood & Highland
Web: visualeffectssociety.com
Contact David S. Cohen at
david.cohen@variety.com