Issue link: https://digital.copcomm.com/i/57248
n n n n CG•Live Action Visual effects artists surrounded actors shot on greenscreen stages with digital cockpits, glass windshields, and the environments outside the cockpits. supervised animation throughout, using their work on the opening sequence and other shots throughout the film as a guide to establish the look and motion of the planes. "Every company had a different pipeline and would eventually render in different ren- derers," Hammack says. "So we distributed base models and textures; we provided a look- dev environment—the HDRs—and a turn- table result. Then, we judged the results visu- ally against our turntable; it didn't matter how they got assets through their pipeline. That was a bit of a challenge for them." The challenge was due, in part, because some of the facilities used raytracing software, while ILM typically uses Pixar's RenderMan. "Our turntable assets are heavy—heavy in de- tails, in the maps, and in the textures," Ham- mack says. "And we have RenderMan tricks and tools we use to do things like multiple bounces and reflection bounces that we tune for efficiency—things some raytracers don't need. They flip a switch and let the light bounce as much as they want. But they end up with different details in the shadows and occlusion. The differences were most telling in early versions. When we delivered textures, some of the raytracers had difficulty with the fine-grain displacement. And, the P-40s are very dirty, so I think the vendors had to fight against the crispness of raytraced reflections and shadows for those. But all the vendors did a great job matching our turntables, and when we got to the newer planes, the P-51s, which are shiny metallic, and the more bare metal bombers, raytracing was the way to go." To avoid cutting back and forth from one vendor to another, Hammack split the work by reel. "The idea was that even if the various ven- dors shaded a plane slightly differently, the plane would be in a different lighting environment, which was a good way to go about it. But, it caused other problems. In some cases, it would have been better if one company had done all the interiors and another all the dogfights." 32 February/March 2012 On location, the actors sat in cockpits on a greenscreen stage, but the cockpit set was sparse. It didn't even have glass. "Everything is digital except the pilot and the seat," Ham- mack says. "And because the camera is focused on the dialog, the interiors had to hold up under repeated viewing of a very controlled frame. There are probably 400 shots like that." Since the majority of UPP's work centered on P-40s, Hammack gave UPP the P-40 inte- riors and gave Pixomondo the P-51s. "They both did fantastic jobs, but they had to share with each other and with other vendors," Hammack says. "So those assets were the most problematic. Some companies had to start with temp assets and get constant updates as we got closer to the final look." ILM acted as the clearing house for asset transfer, cleaning up assets, packaging them, and sending them on to other vendors. Referencing Reality On location, the crew filmed mock-up planes on sets that the visual effects studios would later extend digitally by adding, among other things, more planes. "We had to match the look, and it was tricky," Hammack says. "One mock-up would look more different from the next than you'd want it to. We had to retouch the practical planes to get a consistent look." The crew filmed five real planes landing, taking off, and banking, and shot the actors in planes, as well. "The photography of the actors in planes was a tremendous reference," Hammack says. "But, it was rare that the real planes were in any shots in the movie." Hammack also spent hours looking at documentaries from World War II, attended air shows, and consulted experts. "There were times when we could speak to the Tuskegee Air- men and hear their stories firsthand," he says. "And, we had access to a pilot named Ed Shi- pley, who flies in an acrobatic P-51 air squad." Shipley came to ILM, showed the animators footage of the planes, and reviewed shots. "He showed us what the planes can do and can't do, and how to fly them," says Paul Ka- vanagh, who supervised the animation for the show along with Peter Dalton. "We all got a lesson on flying a P-51 in our chairs. When a plane comes in to land, he told us how many notches he would give the flaps and what that would look like. We animated the flaps accordingly. He would look at our work and critique it, telling us, for example, the planes Reel One: PixOmOndO "In the first reel, a few Tuskegee Airmen are flying a routine patrol when they encounter a German truck that they destroy, and there's a sequence where they come upon a German train," says ILM's Craig Hammack, visual effects supervi- sor. "Pixomondo created a good sequence of them strafing a plane and destroy- ing the train. When they strafe a boiler on the engine, it explodes and sets off a chain reaction of the train derailing, which collapses into the camera, and then we see a massive explosion from ordinance on the train. Those environments were all-digital. Pixomondo is very experienced in creating CG effects."