Mary Ann Skweres talks with Rhythm & Hues vfx wizards on how they brought the wacky world of Dr. Seuss The Cat in the Hat to life.
For Rhythm & Hues visual effects supervisor Doug Smith, Universal Pictures and Imagine Entertainments The Cat in the Hat was unusual. Smith was involved with the film for 16 months, including pre-production and every day during production -- from call to wrap. Usually its not necessary for a vfx super to be on set daily, but because the project had to fit into a certain price range, questions came up almost hourly that involved decisions with implications for post production.
Most of the sequences had very precise animatics on the production side, but in the editing process, the structure of everything changed. Shots intended for one sequence ended up in another. Elements from different sequences were composited into new shots. It was possible to rotoscope out the actors, put them in a new background or switch out people. According to Smith, this manipulation of images is happening more and more lately because the tools are available.
Smith likes working on films that are a bit goofy and not all blood and guts. The most challenging shots were of the Talking Fish in its environment the bowl and the water.
The hilarious, Talking Fish character is based upon Don Knotts character, Barney Fife, from The Andy Griffith Show. Hes passive aggressive. He lectures people, but is easily cowed when confronted. Craig Talme, the animation director, put Fife material online for the animators so that the facial expressions and behaviors of Barney drove the look and actions of the fish.
Technically sophisticated, the fish took four to five months of work. It is completely ray-traced, reflecting its environment in different layers: a shiny wet surface with different degrees of wetness depending on time out of the water; a slimy, overall, jelly layer; and 3D scales. It also has iridescence. Challenges included having plates move against each other on the fish without intersecting and allowing freedom of movement.
Because of their extensive work on animals, the fish eyes that R & H developed are very sophisticated. They have a large refractive layer in them, so as the eyes move the irises refract differently and pick up light very subtly.
Smith believes his team broke new ground with the self-contained world of water in the bowl. It had to fit into the bowl perfectly. There was splash out from the bowl. Of course there was the reflective and clear nature of water. Six to eight months of research and development went into perfecting the techniques for water reacting to the bowl; reacting to the fish and reacting to its environment.
Another breakthrough, a new process called high dynamic range imagery, or HDRI, was used on the set to gather information. Two cameras with fish-eye lenses were placed back-to-back to shoot an exposure wedge from the position of the CG object. The entire lighting set-up and intensity was mapped out in a series of stills. During post the camera crew and unwanted objects were painted out, allowing the HDRI to be used as a lighting source.
Smith explains the results of using this technology: On some of the fish you could actually see the camera and assistant reflected on the nose of the fish! These are the same problems youd have in production if you actually had a shiny fish there. Thats the level of detail possible. Getting integrated, reflective layers on the fish, or any object for that matter, is an important step.
New technology has drawbacks. Because its all a ray-traced environment, the HDRI process consumes a massive amount of rendering time. To approach a project this way requires a lot of very expensive computer time. Also, developing a new working process can be cumbersome. Nobody knows the exact way to do it.
The concept of the distorted world portrayed in the end sequence kept changing throughout pre-production. The distorted house was the last set built and the last scene shot. For the sequence, R & H created a CG vortex and a clear, jelly-like goo named by the director, chicken fat. Splattering the chicken fat around the room distorts it, causing it to morph. In a series of shots, the distortion actively happens. Various objects come to life as the chicken fat covers them. The couches come alive and undulate. When everything finally settles down, the fully distorted room is a real and very elaborate set.
A large amount of matte paintings were created including set extensions and sky replacements. Toward the end of the show a giant vista of columns and ocean water is revealed. The CG ocean has waves breaking around the bases of the rocks. The scene also has animated, flying book-birds and CG atmospherics for clouds.
The matte paintings turned out to be more difficult than originally thought. The director didnt want absolute reality, but it wasnt a cartoon either. It was a stylized version of reality. Approved drawings that worked in the context of 2D artwork didnt work in 3D film. It took a lot of painful interactions to find the right combination of fantasy and reality.
Tommy Fisher, the practical effects man, built the physical cleaning machine for The Things. R & H added the arms and hands to it. Smith took an interesting approach, using real, practical hands as much as possible. Workers with blue arms would perform the action on set. The artists would split out the workers, leaving the hands interacting. A CG arm was then added between the machine and the hands.
A neighborhood of 22 houses was built in Simi Valley. Streets and sidewalks were put in. The hills were sculpted. Brush was scraped off. Irrigation was added and the hills were seeded.
As the shooting schedule developed, production realized that they were going to begin shooting on set with the house interiors. There wasnt any location photo material for outside windows and doors because the neighborhood was not built. Production needed help in putting together a translight, a giant photo process lit from behind to form a backdrop.
R & H made a duplicate neighborhood using the light art, animatics and a Rhino package that the very sophisticated art department had used to build a landscape with houses that fit into the actual surface area. R & H had samples of all the building materials roofing, siding, chimneys and plastic plants. Eight 10K images were spliced together to make the two translights, 100 feet long x 30 feet high. The geography of the translight and real locations matched almost exactly. The only difference was the planks of the clapboard siding showed up more on the translight than in reality.
A week before shooting the story changed. The concept went from being mostly rainy to almost always sunny. In the end some bluescreens needed to be used, so plates were shot on location for that work.
There are other elaborate shots. A stylized, time-lap rainstorm comes over the house as the camera pulls back from an iconic shot of the two kids in the window. It was done with matte painting clouds in 2D then morphing layers upon layers of clouds and bringing in CG rain. Layers of mattes were also used because the camera movement.
Ultimately Smith and his R & H team of 150 artists created the majority of the 3D work, just under 300 shots. Their combined talents and creativity succeeded in bringing the world of Dr. Seuss to life.
Mary Ann Skweres is a filmmaker and freelance writer. She has worked extensively in feature film and documentary post-production with credits as a picture editor and visual effects assistant. She is a member of the Motion Picture Editors Guild.