Issue link: http://digital.copcomm.com/i/51295
cover story Giant's Matt Madden: the studio's 36x65- foot stage holds over 100 mocap cameras. stage building required to facilitate the perfor- mance, but those set-ups took only a fraction of the time of a practical set build." In early 2009 after Avatar had completed their performance capture work, the Tintin filmmakers converged on the Giant stage. The 36x65-foot space holds over 100 motion capture cameras capable of discerning even the most subtle body gestures. "The natural shape of a volume is lot like a circus tent, which peaks down the middle," describes Madden. "The set builders would take advan- tage of this, aligning the sets accordingly to get the maximum height for the shots that needed climbs or falls." The actors were prepped in custom suits with 50 markers and upgraded head rigs by Glenn Derry and Video Hawks to capture facial motion. "Camera resolution is very important," says Madden, "but the real issue is the effective resolution, which is ratio of reso- lution to visible area covered by each camera. "You certainly don't want any marker to move within a pixel and have it not be detected, so we make sure that camera only sees a certain amount of space to prevent any motion detail from being lost." One key system upgrade from the Avatar shoot was in the realtime performance play- back. Part of it was leveraging faster proces- sors, part of it was more advancement in Giant's software to allow realtime capture of up to seven characters. Madden emphasizes that for performance capture it's not just about the capturing marker data. "It's the solving and retargeting software that creates the character, the edit- ing software and artists who clean up and manipulate the motion without compromis- ing the integrity of the original performance. It's building an accessible database, integration of virtual camera and editorial; so there's lots of pieces to the process." With Avatar, Cameron would capture mul- tiple performances and meticulously edit together the best performances into a scene 18 Post • January 2012 build. Then he would enter that virtual world and do his camera work. For Tintin the work- flow was adjusted to Spielberg's style of live- action shooting. Giant was able to target the motion capture data to rigged character models in the CG environments in realtime. The models, built by Weta (www.wetafx.co.nz), are low polygon, with no facial articulation. As the actors per- form on stage the motion data is retargeted in Autodesk MotionBuilder and synced to charac- ter models that move in virtual environments. Spielberg and his operator shot "virtual cam- era" coverage similar to how he would on a traditional film. Only in this scenario he had three viewpoints: wide and close-ups from reference cameras and, through his hand-held viewfinder, the moving character in the virtual environment. Every take was also slated and recorded into video assist just like any live-action movie. "I had like a game controller in my hands," described Spielberg, "with a TV screen with buttons I could crane up and down just with my thumb. Another button I could dolly right and left with my other thumb." Once a take was approved, Spielberg would often explore different angles with the virtual camera while directing the actors. Spielberg and Jackson could then evaluate the performance and circle the approved takes based on a combination of the CG footage, the synchronized close-ups on the face and the actor's physical performance. Once a scene was completed there was no shipping film off to the lab or even trans- coding. Selects were made and the motion capture data was immediately processed by Giant's internal software and sent to Motion- Builder for the New Zealand-based Weta team to QC and render. The CG render was then directly sent down the hall to Tintin edi- tor Michael Kahn's Avid editing workstation. "Once (Spielberg) was finished coming off the stage," says Letteri, "he had everything he needed to cut. Now you're just traditionally making your selects and putting them in the www.postmagazine.com film. So Michael Kahn actually had everything he needed to cut with." Giant and Weta created an expedited workflow to convert every shot as quickly as possible into a game-level representation of the scene... enough for Spielberg to evaluate the timing and blocking of the action, as well as shot composition. "This cut provided the foundation for Weta to build upon with their magnificent animation, textures, lighting and effects," describes Madden. The main hero comedic and dramatic beats were done in Los Angeles. The more complex actions shots, crowds, like second unit production, were primarily done in New Zealand on Weta's Giant-outfitted perfor- mance capture stage. Early on for the 3D version of Tintin, Let- teri took a couple of scenes from the movie and presented them to Spielberg with differ- ent styles of convergence. "You could stay focused on convergence, which is what we did for most of Avatar, we showed him paral- lel convergence, which is IMAX-style, a couple of other styles, just so he could wrap his head around what the 3D space really is." Working from that the animators got a feel for what Spielberg wanted. "Once we got renders we'd get stereo versions going on early on as well, just in case there were some final changes." Once the performance capture edit was locked, Weta worked for over two years fin- ishing the movie. At the peak of production during the summer of 2011, over 900 people were working on the film. "Usually at the end of a film it's all hands on deck," says Letteri. Park Road Post in Wellington completed final color correction, sound re-recording and final sound deliverables. "I never considered, in the 1980s, to do the film animated," said Spielberg, "but as technol- ogy began to evolve I realized that there was a medium that was going to be the perfect tool and the perfect simile between Herge's art and what the art of Tintin could be as a motion picture."