Computer Graphics World

that we can float into the theater, push back into the screen space, or change the orien- tation of the image," Neuman says. is helps them fix problems—perhaps a frame edge that crosses in front of an object ap- pearing in front of the screen. Moving the frame puts the depth cues back in sync. But, he also has begun using the floating win- dow more creatively, to temper the balance be- tween emotional and stereo depth. "Sometimes if we can just pull out one corner, we can re- tain the proximity we want," Neuman says. "And, we're experimenting with tilting the window during action sequences to create tension. We're sculpting a 3D environment artistically based on where the eyes are drawn and where the action is taking place." At Laika, Coraline director Henry Selick is using stereo 3D to enhance a main story point for the stop-motion animation. "Our main character, Coraline, is a little girl who lives in a bland, overcast place," says Brian Van't Hul, VFX supervisor who won an Oscar for visual effects in King Kong while he was at Weta Digital. "In that real world, we keep the stereo flat. But when she goes to the magical land, we increase the depth to enhance the move. We're using stereo 3D in an intentionally dramatic fashion." Because stop-motion animators shoot their films one frame at a time, in order to create the stereo 3D version, they sim- ply shoot two stills. "We shoot the left eye with the digital still camera and then move it over and shoot the right eye," ex- plains Van't Hul. Compositors layer the stereo images into backgrounds moments the scene to be, how deep into the farthest part of the scene, and where I want the convergent point to be," says Robert Neuman, stereoscopic supervisor at Disney. "Based on those three things, the system sets up the camera positions for us." Neuman continues: "We also have a tool to visualize the floating window within a 3D scene. We can see exactly where the floating window lies. So, if I have an over-the-shoulder shot with a character breaking the frame on frame right, I can grab that floating window within the camera space and pull it out until it's in front of the character." To avoid the cardboarding that can happen when the crew uses a telephoto lens, they have tools that tell them the internal volume of characters. "If a character has a factor of 1.0, it's a nice, round character the audience relates to. If it's .1, or only 10 percent round, that's a problem, and we might need to use mul- tiple camera rigs," Neuman explains. "We also have tools that allow us to view what it would look like with multiple rigs. All the tools we developed in-house work within [Autodesk's] Maya." "We have a huge suite of tools, from image viewing to dialing the depth within Maya, that we're constantly refining," says Rob Engle, senior stereographer at Imageworks. "But one area we're particularly interested in moving forward is the 2D-to-3D conver- sion. The most relevant example is our work on G-Force." In this film, which is scheduled for July 2009, a specially trained squad of guinea pigs becomes a force for doing good. "We're taking 2D plates, isolating elements that would be at different depths within the plate, and producing the other eye's point of view. We slide the elements over to create depth and then fill in the holes that the other eye would see. We're de- veloping a wide variety of tools that allow us to do that. And then, we have the added challenge of putting elements from the virtual world into the plates. And, we're still investigating the techniques we'll need for Tim Burton's Alice in Wonder- land—imagine Beowulf but with live people in a 3D virtual world that's Tim Burton's vision of Alice in Wonderland." Frantic created 200 shots for Journey to the Center of the Earth using Autodesk's 3ds Max and Mudbox, Pixologic's ZBrush, Nvidia's Gelato, and several proprietary tools, including the stu- dio's water-simulation software. For compositing, particularly to work with stereo, the studio created a series of scripts and plug- ins for Eyeon's Digital Fusion 10 that they've named Awake. The studio sells the tools it developed to work on Journey and other films on its FranticFilms.com Web site. "We wrote a completely new pipeline for Journey," says Chris Harvey, co-visual effects supervisor at Frantic with Mike Shand. "The entire movie was shot in stereo, so we had double plates for everything. We could have decided to work on one eye and then ask artists to create the second eye, or we could have had scripts generate the second eye. But, we came up with a third approach. Our artists worked in stereo all the way from track- ing to finishing the shots. We literally worked on the shots with both eyes at the same time stacked side by side or vertically. We called it 'stereo stacking.' It was a huge timesavings." –Barbara Robertson Imageworks turned the CG film Beowulf into a stereo 3D version using techniques honed on The Polar Express and Monster House. November 2008 17 Stereoscopy n n n n

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