Issue link: https://digital.copcomm.com/i/17873
n n n n Visual Effects A combination of practical explosions enhanced with digital models destroyed this procedurally created vision of a shattered dream that takes place in a Parisian café. architecture. Cobb asks how they got there. Ariadne answers that she can’t remember, and Cobb explains that they’re in a dream. He says people never remember how dreams start, and adds that they’re not in the part of Paris she thinks they’re in. She panics and loses control of the dream world she created in her own mind. When she does, the world explodes. Nolan shot the scene in Paris. “We were on Rue Bouchut in central Paris,” Franklin says, “a marvelous 19th century classic Parisian street that Chris Corbould rigged with compressed air canisters that fired lightweight debris. Even though it looked dangerous, he rigged it so Leo and Ellen sit in the middle of things explod- ing around them.” To enhance that practical effect, the camera crew filmed the scene with high-speed cameras at 700 frames per second (fps)—a five-second take slowed to a minute on playback. “Tat gave a slow-motion, antigravity look to the debris floating in the air,” Franklin says. “It shows the physics of the world inside their dreaming mind breaking down and falling apart. It’s a stylized look, not like a bomb go- ing off.” For reference, the filmmakers examined the final scene in Michelangelo Antonioni’s 1970 film Zabriski Point in which Daria, a main character, imagines blowing up her boss’s home. Antonioni represented this by ex- ploding a house, filming it with a high-speed camera, and then projecting it in slow motion. “We wanted to create the same complexity,” Franklin says, “all the tiny fragments you get when you blow up something. But, the prac- tical effects team couldn’t destroy things to the extent Chris [Nolan] wanted. He wanted 12 August/September 2010 cobblestones flying in the air, buildings ex- ploding and shattering. So, we did a lot of CG dynamics. We added levels of detail and com- plexity to the sequence.” Franklin began by working with a rough cut that editor Lee Smith assembled in Quick- Time from footage shot on the street in Paris, using Dneg’s “Clip,” a Linux-based editing tool. “Clip allows me to draw annotations on top of the sequences and animate them over the timeline,” he says. “I could scribble with a pen, like in Photoshop, to show which bits break up and where the debris would go.” After sketching an animated sequence in Clip, Franklin discussed his plans with No- lan and Smith via Cinesync’s remote viewing and approval software. Ten, keeping notes from Nolan in mind, he replaced the ani- mated drawings with placeholder visual effects animations and sent the new versions back to Nolan and Smith. “Te final sequence evolved over six months,” Franklin says. “We’d iterate and iter- ate and iterate again. We’d review the sequence with Chris regularly and, toward the end, every day. It was an interactive, two-way process, and it was great.” Effects supervisor Nicola Hoyle led the group that built the models and broke them apart, working with the studio’s DNDyna- mite, a rigid-body dynamics solver built inside Autodesk’s Maya. Lead effects TD May Leung led the animation team. Modelers used refer- ence photos of material filmed on location to match pieces of debris broken on set. But, they also built polygonal models and broke them apart using the studio’s DNShatter—bits of buildings, cardboard boxes, cobblestones, furniture and tableware from the café, and so forth. DNShatter uses procedurally created patterns based on observed shatter patterns. “We couldn’t have achieved the level of de- tail we have in the shot without these proce- dural tools and a fantastic level of photorealistic rendering,” Franklin says. “But, we also did a lot of work in our version of Apple’s Shake to re-time the slow-motion footage. Te explo- sions start at 24 fps and then slow down, as if damped by a treacle-like medium, to 1000 fps, and hang in the air. Leo (Cobb) and Ellen (Ariadne) are moving around within a mael- strom of debris flying and shattering around them. It was a great sequence. A brilliant com- bination of special effects, visual effects, and fantastic compositing.” Stepping Up When Cobb and Ariadne return to Paris in her dreams, the burgeoning dreamspace architect more confidently plays with “reality.” In this sequence, which appeared in the trailers, we see the buildings in Paris fold up and arc over- head to create a cube of streets at 90-degree angles, with people walking on the “ceiling.” Te visual effects team combined their digital work with a practical effects technique similar to one that helped Fred Astaire dance up the walls and across the ceiling of his apart- ment in the 1951 musical Royal Wedding. Franklin previs’d the shot. As Cobb and Ariadne step up, in effect, onto a vertical plane, they are actually walk- ing on a tilting set built by Corbuold’s crew that has a camera fixed to it. “Te whole set pivoted over and they stepped onto the ‘wall’ at the same time,” Franklin says. “We replaced everything except Leo [DiCaprio] and Ellen [Page]. But, we had to get them really step- ping up to that wall.”