New tech gives stop-motion animation its Oscar moment

It feels as if 3D printing technology just suddenly appeared, growing from an abstract idea to household buzzword in record time. From manufacturing medical appliances to entire structures, it seems like there’s little this equipment can’t create. You can even find the state-of-the-art machines at your local library and college campuses for use by the general public. So how are these devices changing things behind the scenes for film productions? In this case, it’s innovating the art of stop-motion animation and is being pioneered by the duo of Brian McLean and Martin Meunier at LAIKA.

LAIKA’s inventive use of rapid prototyping has enabled artistic leaps in character expressiveness, facial animation, motion blur and effects animation. Through highly specialized pipelines and techniques, 3D printing capabilities have been harnessed with color uniformity, mechanical repeatability, and the scale required to significantly enhance stop-motion animated feature films.

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When the animation studio was the first to utilize this emerging technology in 2006 for the film adaptation of Neil Gaiman‘s Coraline, they were still required to hand-paint the printed products. “We negotiated with [director] Henry Selick on the number of freckles that Coraline would have on her face, since someone would have to paint them,” McLean recalled while speaking with The Hollywood Reporter. Fortunately, by the time they embarked on their second feature, ParaNorman, they were able to upgrade to 3D colour printers; although this presented a whole new set of problems.

Rapid prototyping is a technique used by industrial manufacturers to create draft versions of their products. Consequently, the printers were not designed to calibrate precise colour combinations and required some additional steps to produce the desired quality. Therefore, the team at LAIKA created custom paint chips with Pantone codes — much like the colour samples available at local hardware stores — to use as their colour palette. Moreover since the machines inevitably offer a limited range of shades, they must also layer combinations of colours to achieve a wider selection.

How does it work?

Replacement animation is a process in which parts of a puppet, usually faces or limbs, are substituted for similar but slightly different parts to achieve the illusion of movement. “Having a rapid prototype machine is the equivalent of 20 sculptors working in unison,” said Meunier in an interview with Inside Science. The creators at LAIKA print hundreds of interchangeable facial features, such as eyebrows, eyes, noses and mouths, so animators can switch them to generate specific expressions. This has allowed them to go from approximately 207,000 possible facial expressions in Coraline to more than 44 million in their latest feature, Kubo and the Two Strings, which will be released in August 2016. In addition, they are able to print specialty facial kits that will only be used once during production for a unique performance — a luxury not available when everything is being handmade.

1. The first step is one that generally occurs in any type of animation: a hand-sculpted model is made that not only defines the character’s proportions, but also the unique traits that will make it recognizable and appealing to audiences.
2. Next, the sculpted maquette is scanned to generate a 3D digital version. The character’s expressions are then animated frame-by-frame apart from the body so they can be sent for rapid prototyping. The digital models are intentionally exaggerated to compensate for the softened edges that occur during printing.
3. Each 3D colour printer produces approximately 20 facial components at a time, or less if the character’s head is larger. The printer sprays coloured glue onto thin layers of a gypsum powder that after several hours form the finished pieces.
4. The 3D moulds emerge encased in the white printing powder. Once they are cleaned, the quality assurance team carefully sands and tests each part for consistency as it’s nearly impossible to guarantee accurate and uniform results without post-processing. The quality of the product can be affected by everything from room temperature to humidity to printer maintenance. They are then dipped in superglue to harden the shape and enhance the colour.
5. The faces are carefully catalogued and stored in a face and parts library until they are required by animators. The selected components are then attached to what is essentially a plastic skull produced by the same rapid prototyping process, but using a non-colour 3D printer. This allows filmmakers to repeatedly swap the independent elements as needed to create the desired expression.
6. Finally, each photographed frame is digitally corrected to remove the seams visible between the interchangeable components. (This step was noticeably not performed in Charlie Kaufman’s Anomalisa.)

This art form, which involves moving and photographing characters one frame at a time, dates back more than a century. Many may be familiar with Ray Harryhausen’s stop-motion creations in King Kong and Clash of the Titans, or the technique’s use in holiday specials such as Rudolph, the Red-Nosed Reindeer and Frosty the Snowman. But LAIKA is revolutionizing the age old technique by merging it with 21st century technology and creating seamless pictures that showcase the magic of physical environments paired with computer advancement. With the employment of painstakingly built sets and meticulously crafted characters, animators are able to produce an average of six seconds of footage per week — it’s certainly not a fast-paced job, but it’s one undoubtedly performed with love and devotion. And their efforts have not gone unnoticed: all three of the studio’s features — Coraline, ParaNorman and The Boxtrolls — have been nominated for the Academy Award for best animated feature.