3D Artist
Feb
13

The VFX of Kubo and the Two Strings

News & Features
by
Ian Failes

We go behind the scenes of Laika’s award-winning animation

The VFX of Kubo and the Two Strings
© Images courtesy of Laika/Focus Features

Laika, the studio behind Coraline, ParaNorman and The Boxtrolls, is already a household name in stop-motion animation. But with each new release, Laika, which is based in Portland, Oregon, has continued to innovate in 3D printing, rapid prototyping and the use of seamless 3D and visual effects in bringing its animated feature films to life.

Laika’s latest award-winning animated feature is Kubo And The Two Strings, directed by the studio’s president and CEO, Travis Knight, who led a team of artists to up the ante. This time around, the studio made further leaps in advancing the art of 3D colour printing, employing larger and more complex stop-motion puppets and using 3D and visual effects for ever more complicated worlds and characters in its storytelling.

Kubo And The Two Strings is set in ancient Japan and tells the story of a young boy called Kubo (voiced by Art Parkinson) who must find a magical suit of armour that belonged to his father. Telling a samurai tale was well-suited to Laika’s production methodology, according to Knight: “The fact that we blend the physical and the digital, that we fuse craft and art and technology – that’s really unlike anywhere or anything else in the industry,” the director says. “But our goal today really is the same as when we started out ten years ago, which is to make movies that matter; to craft meaningful films that are bold, distinctive and enduring, and to do so in a way that revolutionises animated film-making.”

The VFX of Kubo and the Two Strings
© Images courtesy of Laika/Focus Features

However, it wasn’t always easy to create revolutions in stop-motion. In fact, Knight himself admits that before Coraline was released, stop-motion was a “dying art form”. It took time (read: money) to make characters and sets and then to animate them. Plus, stop-motion had limitations both in the scope and in getting the most out of character performances. But with Coraline and the films that followed it, Laika found ways to make the process both more efficient and more spectacular.

One way was through rapid prototyping. Laika would actually build 3D models of its characters and use those models to carry out facial animation. Each of the expressions made in the computer are then replicated in 3D-printed face parts. The studio uses a replacement animation technique where the pre-fabricated face and other pieces are replaced frame by frame, with high precision and repeatability. It’s important, though, to note the approach still employs the unique skills of Laika artists in sanding, spray coating, magnetising and hand-painting characters before they can be animated on a soundstage.

The inventive use of rapid prototyping was so innovative that it earned Laika’s Brian McLean and Martin Meunier a Scientific And Engineering Award from the Academy of Motion Picture Arts and Sciences in February 2016.

The VFX of Kubo and the Two Strings
© Images courtesy of Laika/Focus Features

On Coraline, Laika relied on a 3D printer from Stratasys to make 3D puppet pieces. The printer produced neutral plastic pieces, which meant everything still had to be hand-painted. For its next films, ParaNorman and The Boxtrolls, Laika sought out a colour printing solution. Instead of plastic, the resulting prints were made from resin powder. This provided less accuracy and repeatability, although the studio was able – through continued hand craftsmanship – to produce a myriad of character faces.
By the time Kubo came around, Laika’s confidence in rapid prototyping and 3D printing had increased so much that there was no holding back with character designs. In particular, when McLean saw the designs of some of the key characters such as Monkey (voiced by Charlize Theron) who has fine hair; Beetle (Matthew McConaughey), who has a sharp edged-face; and the Moon Beast, a complicated sea creature-like monster, the head of rapid prototype looked for yet another 3D printing approach.

Stratasys developed a new three-colour printer that printed in plastic and Laika took delivery of what was a machine still in beta. “Immediately,” recalls McLean, “I started getting very excited because all those benefits of printing in plastic were rushing back through my mind thinking we could have colour consistency, we could have fine feature detail, we could have repeatability.”

Realising the new printer’s capabilities could be taken even further, Laika partnered with Stratasys on the 3D software side. This gave the studio the ability to add gradients to the colour printing and other effects for those three characters – Monkey, Beetle and the Moon Beast. Even with only three colours at their disposal, “we could take Monkey and get a wonderful sculptural detail but have it still look the way the director wanted,” notes McLean. “And that’s the amazing thing about looking at Monkey, you’d never guess that she consists of only cyan, magenta and white.”

The Moon Beast was also a great beneficiary of Laika’s new 3D printing approach. It was the studio’s first fully 3D printed character ever, made up of over 881 individual parts, 130 of which are colour 3D printed and 751 being a combination of metal body and leg armatures components as well as internal dressing pieces.

One of Laika’s artists even hacked the printer’s capabilities to add some translucency into the final Moon Beast design. “Even though these machines weren’t able to do clear at the time, we tricked them into thinking they could do clear printing,” states McLean. “We put a clear resin into a coloured slot in the machine, and told the machine to print red, but really it printed clear. It gave the creature some wonderful qualities, including clear little windows that would allow for shimmer and glimmer as it swam through the moonlight.”

The VFX of Kubo and the Two Strings
The VFX of Kubo and the Two Strings
© Images courtesy of Laika/Focus Features

Animation traditionalists might consider any digital augmentation to be against the spirit of stop-motion, but to Laika the use of computer graphics and visual effects now forms a key role in telling its stories. The use of visual effects in Kubo varied, from fully digital characters and environments, to compositing in layered stop-motion animation, to minor fix-its. All the while, notes Laika visual effects supervisor Steve Emerson, “we always make sure that we’re doing that work in a way that is honouring the craft of stop-motion animation.”

An example of how Laika combines practical and digital can be seen in Kubo with the Hall of Bones sequence. Here, the characters encounter an enormous skeleton. At 400lbs and 16 feet from head to toe with a 23-foot wingspan, it was one of the largest stop-motion puppets ever created. But even then visual effects still had a place in extending the Hall of Bones puppet, which had been filmed against a green screen.

Visual effects and 3D played a key role, too, in adding in environments and effects that could never be achieved with stop-motion. This included an ocean simulation, inspired by famous Japanese wood block print artist Hokusai’s The Great Wave. Although Laika could have engaged in an absolutely photorealistic depiction of water, Emerson notes that that approach would not have belonged in Kubo’s world. So, again looking to draw from the physical world, Laika shot some practical water tests on its stop-motion stages.

The VFX of Kubo and the Two Strings
© Images courtesy of Laika/Focus Features

“One test we did in particular,” outlines Emerson, “was to take an iron mesh grid, and then drape different types of materials over it, different types of fabrics, reflective and non-reflective. Even [with] an almost garbage bag-type of material where it would cling to that grid we would get this really interesting kind of scoop patterning that everybody was really liking. So we had physical reference, we had some amazing artwork and then we got to work in visual effects. Ultimately we ended up with a system that combined fractal displacement with ocean simulations.”

Another of the visual effects team’s roles on any Laika film is to do a range of ‘cosmetic’ work on the puppets and the final frames to deal with artifacts that come out of the 3D printing and stop-motion process. An entirely new development on Kubo, however, was some VFX augmentation directly related to character empathy. Laika’s character puppets have eyeballs with eyelids that are animatable. Due to the facial replacement process in animation, a small gap near the eyelid would be visible in the final frame.

The VFX of Kubo and the Two Strings
© Images courtesy of Laika/Focus Features

“Early on we just blended out that line to make it feel more human-like,” explains Emerson. “We bought ourselves about 1,500 more shots, but, it’s funny, most people to whom I mention the fact that we’d done this additional eyelid blending don’t even realise that we’ve done it. And so for me that means we were successful.”