Animating the World of 'Miss Potter'

In Miss Potter (opening Jan. 12 from The Weinstein Co.), director Chris Noonan explores the life of Beatrix Potter (Renee Zellweger), author of many best-selling children books. The magical quality of Potter's creations is emphasized by some exquisite animation work in which her drawings come to life, initially with subtle twitches and gestures, eventually with more complex interactions. To bring Potter's beloved creations to life, Noonan turned to Passion Pictures for the animation (supervised by Alyson Hamilton), and to Cinesite (Europe) for its seamless integration into live-action plates.

"We did 70 shots, including about 75% of animation shots," recalls vfx supervisor Simon Stanley-Clamp, who oversaw the entire project, with vfx producer Clare Norman. "Our main challenge was to match Beatrix Potter's original illustrations precisely. We had to reproduce the watercolors, the ink, the pencil drawings. From the beginning, we knew there were specific drawings that we had to match. Director Chris Noonan and production designer Martin Childs had selected several pieces of work that had to be integrated in the movie, either as an illustration that Beatrix Potter was working on, or as a magical 'vision' from Beatrix's dreamy point of view. We were lucky enough to have access to most of Potter's archives. We could then have the real illustrations for reference, which was an invaluable help."

Timing the Animation

For all the animation shots, the first step was to storyboard the action with an original illustration as the starting point. Working with Noonan, the team selected characters and storylines for specific animated sequences. The group discussed printed images and ideas for how the illustrations might move and interact with actors in specific scenes. The storyboards were then turned into key frame pencil drawings that were timed out. Played back in QuickTime format on a Mac, the crude animation helped the actors adjust the timing of their performance on set. When Zellweger had to physically interact with a character with her brush or pencil, Stanley-Clamp supplied exact scale reference of the character at key positions on the paper as a blue key line. This reference was then removed in post-production.

"In one shot, Renee had to chase a rabbit across the page as he runs away from her brush," Stanley-Clamp says. "There actually were three key positions on the page -- start position, mid position, end position -- that she used to time the movement of the brush across the paper. The outlines were then painted out. In other shots, the paper featured a thinly printed blue tracking grid that allowed the team to precisely track the perspective of the piece of paper later on. Production had made it clear that they didn't want visual effects to interfere with the shooting in any way. Since this was not an effects-heavy film, we had to keep a very low-key approach on set, which included avoiding laying down hundreds of tracking marks. So, we had to find alternatives that didn't interfere with the performances."

One of the technical issues that Cinesite had to address early on was the anamorphic format of the live-action footage. In order for Passion Pictures to create the animation, the footage needed to be flattened. The plates were scanned at 4K resolution, and a custom written tool was created to flatten and downsize the material to 3K (3656x1556). Once the shots had been completed, they were re-anamorphosized for the digital intermediate. Early on, the decision was made that the animation would be produced flat. The three-dimensional quality of the illustrations would be added in compositing.

Warping and Mapping

Passion Pictures first produced keyframe pencil line tests that represented every four or eight frames of the animation. The drawings were then scanned and delivered to Cinesite to be used in temp composites. "We checked if the timing was right. Once this was confirmed, the in-betweens were produced, cleaned up and scanned into Softimage's Toonz. The finished animation was then output as .tif files. Each character had its own color separation, which allowed compositors to color-correct them individually. On top of the RGB layers, the characters also had their own matte, a specific line pass to replicate the pencil look and a color wash for the watercolors. The animation was imported into Shake, our compositing tool, where all the layers were carefully blended together. One of the key aspects was tracking the live action plates. There was one shot in which we had to insert 12 moving illustrations into a moving plate, including one that flies across the whole screen. We used Area Track, our in-house Shake motion tracking plug-in, to lock the animation onto the live-action pages. From the motion analysis, we output a camera node for each of the illustrations. The result is absolutely fantastic as the animation is really locked into the plate. Then, we make extensive use of warping and mapping techniques to make the animation fit the perspective of the paper."

When the paper featured a tracking grid, the entire page was replaced by a digital replica created from a scan of the original watercolor paper. It was then matched to the lighting of the scene, while shadows were lifted from the scene and added back over it. "We worked a lot to retain the specific quality of the watercolor paper, but the hardest part was balancing the composite to match the original illustration. When we shot an animation scene on set, we brought the original Beatrix Potter illustration with us and filmed it in the same lighting conditions and at the same angle. This plate then became the absolute reference that we had to match with the compositing. Our compositors also had a high-resolution scan of each illustration on their computer to allow for precise color and texture comparisons."

In one shot, a frog character named Jeremy Fisher leaves the plane of the page and physically grabs the end of the brush that Potter is using. In order to give Zellweger some resistance to react to, Stanley-Clamp actually played the Jeremy Fisher part by holding the end of the brush with two fingers. His fingers were later replaced with Fisher's animated hands. "We had a lot of discussions about whether or not Jeremy should have a shadow... He is two-dimensional, but then he's lifted off the page... And if he did have a shadow, where should it fall? Should it be hard or soft? Should it be blurred? We did a lot of fiddling around to get the shadow right. We ended up warping the animation matte in Inferno to create that shadow element. It was a real artistic challenge as it was probably the shot where Beatrix's characters get the most three dimensional, but we didn't want to end up with a Who Framed Roger Rabbit look."

A Rabbit-Drawn Pumpkin Carriage

The most "magical" shot of the entire movie appears in a scene where a young Beatrix dreamily looks out of her window and watches her parents leave for a party. Her imaginings spread into reality and she sees her parents mounting an exquisite, rabbit-drawn carriage. The composition of the shot precisely replicates an original pencil drawing by Potter. The plate was filmed with a huge Chinese lantern hung over the ground to cast a soft orange glow. Two practical gas lanterns were also filmed, at the point of entrance on the carriage door. "There actually wasn't any carriage at all," Stanley-Clamp remarks. "The actors just walked through a plain black door on top of three black steps. This helped us position the animated carriage later on. On the ground, we had a tracking marker for each one of the rabbits. For these characters, we discussed using 3D animation, but we eventually thought that it would be too much of a departure from everything else in the film. So, we went back to the illustrated look. The three-dimensional look was obtained through nice matte work, subtle shaders and additional shadows. The front row of rabbits had a red-green-blue color separation, while the back row had a green-blue-red separation. So, we could separate off each individual rabbit, and the shadow pass from the front rabbits onto the back rabbits was generated through that mask. In order to match the soft and warm light of the live-action plate, the final composite was color graded through a graduated mask with the pumpkin carriage at its center point. This allowed the light to softly fall off on the rabbits." Parallel to this effort, the set was digitally extended with a matte painting.

Non-animation visual effects shots include a series of beautiful scenes in which a steam train is seen traveling across stunning locations. A tourist train was shot as a reference for scale, speed and steam, but it was ultimately replaced with a period-accurate CG train modeled in Maya. Several takes across different times and lighting conditions were shot, and the best of these were selected and combined. Steam from the original train was augmented, and lighting conditions altered for the final composite.

"Technically, it was not a complex show, but it was definitely most difficult to get right on an artistic level," Stanley-Clamp concludes. "If we went too far in one direction, the animation would look cartoony; in the opposite direction, it would look like 3D animation. It was a very fine balance that we had to find in the compositing."

Alain Bielik is the founder and editor of renowned effects magazine S.F.X, published in France since 1991. He also contributes to various French publications and occasionally to Cinefex. In 2004, he organized a major special effects exhibition at the Musée International de la Miniature in Lyon, France.