Because production couldn’t build a set that big, Elf village miniatures were re-used for the Elf musical number. The village was mapped out digitally. Dneg assisted in pre-vizing the sequence and translating it to Moco rigs for the bluescreen shots of the Elves. Actors performing the musical number were shot on a bluescreen stage in the right angles and positions then composited into the miniature set.

Visual effects supervisor Simon Clutterbuck and visual effects producer Martin Hobbs headed up the team at Moving Picture Co. (MPC) that created the talking snake Heston, wicked sidekick to Ella’s villain. O’Haver thinks it’s one of the best digital characters he’s ever seen. “I love Heston because he harks back to my love of cartoons and he reminds me of all those great evil sidekick snakes, from Sir Hiss in Robin Hood to Kaa in Jungle Book, but he has a personality all his own,” he says. “Watching him be created was something new for me and a magical experience.”

To achieve practical interactions, eye-lines and framing, Heston was originally conceived as an on-set puppeteered snake enhanced by computer animation. Despite a perfect physical design, the animatronic snake had physical limitations. It lacked the facial and skeletal movements necessary to bring the snake to life and had to be supported by a chair, a candlestick or other objects as originally depicted in the storyboards.

The shoot was already underway when MPC’s lead animator Tony Thorne and lead rigger Matt Hicks carried out animation tests of an entirely computer generated snake. The results convinced O’Haver and Bickerton that a fully digital character would result in a more dynamic performance. With the physical limitations removed Heston could slither around on the floor and react with other in-shot props. The MPC animation team was given the chance to fully develop the character. Bickerton comments, “Texturing and boning of Heston was superb and MPC were magnificent in their enthusiasm and speed.”

The Moving Picture Co.’s job was to make the movement of Heston the snake look as real as possible. Courtesy of The Moving Picture Co. © Miramax Films.

MPC’s rigging and shading toolsets were expanded to meet the challenges presented by the snake. John Haddon developed Heston’s skin shader. Emulating the properties of real snakeskin, it permitted secondary wrinkling and buckling in the body, mirroring the behavior of real large snakes like boas. Composite supervisor Angela Barson developed a method to allow the compositors full control when matching Heston with the background plates, many complicated by flickering flames. For each shot of Heston, nineteen separate passes were rendered and subsequently combined in Shake. Interactive lighting was applied to each composite by manipulating separate layers such as the specular, sheen, occlusion and directional lighting passes. The 2D look was kept flexible to allow adjustments in 2D, removing the need to revert back to 3D for re-lighting. To allude to the light scattering around the thinner parts of the snake’s skin, MPC developed a rough pass based on skin thickness that subtly enhanced brighter regions of the background plate in the areas around the nostrils and open mouth.

Cinesite (Europe) Ltd., headed by visual effects producer Ken Dailey and visual effects supervisor Sue Rowe created Benny the Book, the holographic person trapped inside a book. About 60% of the work (roughly 50 shots) was about the 3D Benny, the rest was compositing. On a bluescreen day, the team covered a lot — about a 120 shots. They were very disciplined and got every bit of dialog that the character might say. Every eventuality was planned for so when the editing occurred, Cinesite had all the footage necessary to create every Benny shot.

The biggest challenge for the Cinesite team was getting the effect of photo-realism. For Benny to look like a hologram meant that he would need to be seen in three dimensions. The character needed to become a virtual actor. That necessitated being tracked into each shot and creating a 3D build. The impressive results achieved by the team belie the fact that photo-realism and human characteristics in 3D are notoriously hard to do.

The team had one day of shooting on a bluescreen stage with actor Jimi Mistri. A locked-off camera with a long lens shot Jimi straight on. No perspective changes were captured, but facial expressions were captured. The facial expressions in that footage were used as a texture map projected onto a 3D scan of the actor’s head. The second camera on a Milo rig shot from a best guess matching angle to background plates. When possible the team tracked this 2D angled footage to the cover of the book. If the book angle changed a lot, the 3D head was used.