THE REAL-TIME VFX IN THE BFG
Meet the Weta Digital team that brought Roald Dahl’s classic to life
Rather than relying on a variety of visual effects vendors, filmmaker Steven Spielberg recruited Weta Digital to produce all of the 875 VFX shots needed for his cinematic adaptation of The BFG, which revolves around a giant kidnapping an orphan and taking her to his fantastical homeland. “Our goal was to be as invisible as possible and let the technology empower the actors,” states Weta Digital VFX supervisor Guy Williams. “In the beginning we thought if the BFG is our hero then the other giants are antagonists that need to be dark and evil. This wasn’t the case for Steven. They look at the BFG as the runt of the litter. There had to be this chance of warmth in the other giants even though they mock the BFG. Fleshlumpeater has a bunch of conversations with the BFG. I thought that was a beautiful choice made by Steven. It makes you understand the dynamics of what life is like for the BFG.”
real-time capture
Motion capture was utilised to digitally realise the title character, portrayed by Mark Rylance, and his enormous siblings, who are encountered by Sophie (Ruby Barnhill). “One of the differences on BFG was whenever Mark and Ruby are acting together, we’re capturing and rendering him in real-time and putting Mark’s BFG back into the main unit camera as a 24 foot tall giant with Ruby,” explains Guy. “It allowed Steven to get an idea of the framing of the shot without having to guess.” Getting the right eye-lines was not a major problem. “We had this thing called The Tower, which was a big truss work construct that the grips made for us. It was roughly 16 feet tall with an 8 by 8 foot platform. Motion capture cameras and Mark were placed on top of The Tower, which was moved around the stage to where the BFG would be in relationship to Sophie.”
As you would expect on a giant-centric film, scale was one of the main challenges the team faced. Guy explains: “The BFG and Fleshlumpeater are 24 feet tall and 50 feet tall, respectively, and Mark and Jemaine Clement are both only 6 feet tall. To get the right scale, we would shoot it in three passes. We would shoot body passes for Mark and Fleshlumpeater, and if we had Sophie, [we’d] then shoot a live-action pass of her; the trick of this being we never wanted to force the timing. In other words, we didn’t rehearse it 25 times
until they got it right on three different scales. Even when we’re shooting Mark at the wrong scale we’re doing facial capture for him because we wanted to use snippets [later on]. Often we’d be able to use performances from all three different passes.”
Designing the giants
A balance needed to be maintained in the design of the nine giants. “Rick Carter [production designer], Steven and Weta went through iterations to find something that felt real and not cartoony but at the same time they had to be personifications,” remarks Guy. “The giants couldn’t be 50 feet tall humans because there wouldn’t be a point to doing the movie. Steven also wanted them to feel fantastical to some degree.”
BFG needed to convey a sense of warmth but with an edge to him, says Guy: “The way Steven kept describing BFG needed to convey a sense of warmth. The way Steven kept describing him was ‘like a friendly grandfather’ him was like a friendly grandfather. We made him a slightly older man because he’s 2000 years old. It is possible to have an intimidating character when he frowns but he can also light up a room with his smile. That was the balance we were aiming for. It came down to how the beard worked, how the hair flowed on the head, and how scruffy we made his hair.”
When it came to rigging the BFG, it was easier than expected, because he’s humanoid character with only a few fantastical choices in the character design. “The only thing that was weird about him was that by design his neck is more serpentine. It has a rather pronounced curve,” explains Guy.
The difficultly was in capturing the warmth conveyed by Mark Rylance’s performance. “It all comes down to understanding and patience. You have to understand how Mark does it and then have the patience to get it right.” Guy adds: “The only challenge with the other giants was that their legs might be shorter than on a real human and their torsos might be a bit wider. They were more of a caricature of their forms. It was more of a design challenge than a technological one.”
Digital clothes show
Extensive detail was incorporated into the wardrobe for the BFG to create a realistic depth to the character’s look and movement.
“He has three layers of clothing stacked on top of each other and it’s all simulated,” states Guy. “We put so much detail into the clothing. There are little threads hanging off from the seam line which are simulated so if a breeze goes by they flutter in the wind.”
Physical costumes were constructed as a reference for the CG artists and the actors. “For the BFG, Joanna Johnston [costume designer] made a costume that could fit on Mark Rylance, so he became the model for him. We built eight foot tall marquettes that they
could dress the costumes onto for the giants. Once we had built all of the costumes, then we could look at them. They gave Steven something that he could walk around and say, ‘I like this colour. I don’t like that.’”
A lot of the lighting and colour palette came from the concept artwork created for the movie by the production team, but Guy explains how cinematographer Janusz Kaminski took it a step further. “He used the Simulcam to see where the key light sources in the environment were. Janusz would take a look at it and say, ‘There’s a window off to the left and a fireplace on the right.’ He would start lighting the live-action set to match into the CG set.” Props were built as a point of reference, too. “In the cottage, we built the windowsill or the table Ruby stands on but when it comes to the rocking chair and the room itself that’s all CG.”
Size also works both ways, as small eight feet wide miniature sets were constructed by Weta Workshop to plan out the shoots. “They gave Steven a chance to walk around and say, ‘I don’t like that tree, that walkway isn’t wide enough.’ The miniature sets allowed us to solve a lot of problems before we started to build them digitally.” The BFG is in cinemas now, watch the trailer here: www.bit.ly/3dworld-bfg