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A key contributor to all the Harry Potter movies, MPC produced 230 shots, including the nose replacement on actor Ralph Fiennes who plays Voldemort. All images © 2007 Warner Bros. Ent. Inc. 

Although Double Negative did the bulk of the work on Harry Potter and the Order of the Phoenix (which opened July 7 from Warner Bros. Pictures), overall visual effects supervisor Tim Burke spread more than 500 shots among seven different vendors. Leading the pack was The Moving Picture Co., a key contributor to all the Harry Potter movies. Greg Butler supervised the effort, with vfx producer Jay Heapy, and supervisors Charley Henley, Clwyd Edwards and Ferran Domenech. The 230-shot assignment included a series of nose replacement on actor Ralph Fiennes, who plays the evil sorcerer Voldemort, an eerie effect that MPC had pioneered on the previous film. "We were able to re-use the original assets, including the facial rigging set-up and the textures, with some updates," Butler notes. "We used our new sub-surface scatter model that allowed us to obtain more realistic results much faster. On set, Ralph had tracking markers on the face that we used to track on the CG nose. The digital appliance went from his eyes down to the upper lip and was about three inches wide. We always tried to keep as much of the real skin as possible."

Further to the nose-less effect, MPC was asked to tackle the final confrontation between Voldemort and Dumbledore. When the evil sorcerer cast a fire snake, Dumbledore retaliates with a water bubble. Both manifestations made large use of Flowline, a fluid simulation engine developed by Munich-based Scanline. "We used Flowline on Poseidon, and actually, the fire simulation in Order of the Phoenix was very similar to the oil fire effect that we had done for that film," Butler observes. "We had great support from the Scanline team who worked a lot to adapt the software to our needs. For the fire creature, we started by doing keyframe animation on a snake geometry using Maya. Once we got approval for the performance, we took it into Flowline to generate the fire. With this in mind, we had included lots of cracks in the surface in order to justify the emission of hot gases that would all ignite. Since the fuel was constantly emitting out of the body, the fire reacted organically to any movement that the creature did."

MPC used Maya's particle system and RenderMan's firework shader to create the effects in a comedic sequence where Ron's twin brothers Fred and George launch a series of magical fireworks at their new Headmistress. 

On Dumbledore's side, the giant water globe was created as a displaced sphere rendered with many Flowline fluid and particle simulations. For the shot of the bubble bursting, MPC used a filmed element of a big dump tank on set. On all the shots, the company employed RenderMan for rendering, and Shake for compositing.

Parallel to their "creature" work, MPC tackled major set extensions for the Ministry of Magic, a huge location in which the final battle takes place. The geometry was modeled based on blueprints, with finer details provided by a LIDAR scan. Then, MPC did an extensive photo survey of the set, using multiple exposures and a flat lighting. These images were then employed as color maps for projection onto the geometries. Then, a shader applied all the highlights and reflections. "The set ended up being so huge that we had great difficulties to render it," Butler notes. "There was so much geometry and textures, so many lights, so much ray-tracing, that it took us months to figure out an efficient way to render it all procedurally... " Later on, in-house rigid body dynamics system PAPI was used to simulate hundreds of windows explosions on the digital set. In another sequence, MPC did a complex set extension on the seemingly endless marble staircase -- a CG environment except for the area surrounding the actors.