DOCTOR STRANGE
Trevor Hogg meets VFX supervisor Stephane Ceretti to discover the magic behind Marvel’s latest blockbuster
Discover how Marvel Studios created the CG magic of Doctor Strange
One can never say that the Marvel Cinematic Universe has been without its creative difficulties. For Marvel Studios’ visual effects supervisor Stephane Ceretti, the challenge has been going from producing a photo-real CG raccoon for Guardians of the Galaxy to folding cities in Doctor Strange. “It’s different! The racoon had its challenges and this one has its own challenges as well.”
Unlike Guardians of the Galaxy, which dealt with a group of galactic misfits coming together to save the universe, Doctor Strange revolves around a physically and spiritually crippled world-famous neurosurgeon Dr. Stephen Strange, and his discovery of a mystic place known as Kamar-taj that leads him to become The Sorcerer Supreme.
“Guardians finished August 2014 and we started this one in September 2014,” recalls Stephane, who went immediately from collaborating with filmmaker James Gunn (Super) to Scott Derrickson (Sinister). “Scott was already on the project starting to write the script, and had collected a huge amount of visual references on the web and from books. He had a lot of ideas in mind about what the magic would be and what it would do, but was also open to new ideas. Charles Wood, the production designer, was really involved with all of that too. There were so many things in the film that we had to tackle from the astral projections to the dimensions they visit. We wanted to have a full overview of everything that we would have to deal with.”
Getting started
Storyboards, techvis, previz and postviz were extensively utilised. “Charles does a lot of concepts even in terms of key frames, which the visual development department at Marvel also creates,” explains Stephane. “As soon as we had a good idea of the script and the story beats that we would have to deal with, The Third Floor was brought in to start to build all of these worlds and work on the sequences in previz. We were using concepts as a base and then animated them so we had understanding of how things would look, but also how they would move. It was important for us to get the key players working together to get all of these things going because it’s such a dynamic and evolving process.
“Previz/postviz was led by Faraz Hameed from The Third Floor and a lot of it was also worked on in close conjunction with Marvel’s editor, Wyatt Smith, who came on the project before production started to shoot. Around 1,400 visual effects shots needed to be produced. “All of the shots have little tricks and are different from each other,” says Stephane. “We always tried to bring new ideas to every shot. Every shot had it own R&D.” Achieving a balance between fantasy and reality was an important goal for the production. “That was a big thing for Scott,” remarks Stephane. “We always tried to relate magic to something that is physically correct. For example, we have a type of magic in the film called Eldritch magic. They open these sparkly gateways that are used to go from one place to another. It’s all based on long exposure photography and physical objects that people can relate to. If we use a material that is going to distort and change itself, like moving and bending buildings, we wanted to make sure that they look completely physical in their movement,” he says.
Whipped into shape
In the film, there are different types of Eldritch magic and Doctor Strange, played by Beneditch Cumberbatch, can draw mandalas in front of him: “He uses Eldritch magic to create Rune Shields to protect himself when fighting. Then there’s what we call the Eldritch Whip, which is created by Doctor Strange to battle the Zealots,” reveals Stephane.
Interactive lighting helped with the creation and integration of the Eldritch Whip. “It looks like a stream of energy with lots of sparks, and when it hits something it sears and burns. We had some LED strips in Benedict’s hands so we could get a little bit of light on the hands and face when Doctor
Strange is using it. We also had a LED whip for fighting. It was like strings of LEDS put into some gel so they wouldn’t break.”
Mixed into VFX was the ability of Doctor Strange to handle the magic. “The main arc of his story is him learning about magic, being a bit clumsy and not that good at it. But through trials and tribulations, he becomes the real Doctor Strange. It’s a big thing and we played that story in terms of the effects, like with the Cloak of Levitation.”
“Doctor Strange finds the Eye of Agamotto in the Kamar-taj,” remarks Stephane when discussing the mystic artefact of wisdom residing in an amulet that enables its wearer to see through illusions and to create gateways to other dimensions. “He’s carrying that around his neck. I won’t go into too much detail about what Doctor Strange does with it. But I will say that the Eye of Agamotto is quite an important thing in the film.”
Another key storyline element is a fictional grimoire. “There are tons of books because there’s a library in the Kamartaj and that’s how he learns about magic. There’s the Book of Vishanti [contains spells of defensive of magic] and The Book of Cagliostro [a collection of mystic knowledge gathered from numerous sources] is the most important book in the film.” The path of learning does not always go easy for the apprentice sorcerer, who accidentally conjures a crystal effect. “Doctor Strange is not a patient student. He’s playing around with one of the spells and in this case it doesn’t turn out well.”
Fractal worlds
“We do a lot of Kaleidoscope effects,” reveals Stephane. “It’s going back to magic and optical illusions. We do a lot of things with 3D fractals. There’s a shot in a church where it seems to be all changing and we call it Mandelbroting [in honour of the
all of the shots have little tricks and are different From each other; We always tried to bring new ideas to every shot, and every shot had its own r&d stephane cerrati, visual effects supervisor, Marvel studios
mathematician Benoit Mandelbrot who invented fractals]. Basically, the Zealots have the power to change the shape of the world and when they do that it turns into a big fractal world.” Buildings fold over each other harkening back to the signature visual effect in Inception. “It’s definitely a point of reference but we’re pushing it much further than before.”
Rendering was a major issue for the mind-bending urban scenes. “We had a full digital version of new York and bent entire streets. We did same with London. It was a huge amount of assets that we had to build.”
A pivotal environment that needed to be digitally and practically conjured was the mysterious enclave of Kamar-taj. Situated in the Himalayas, Kamar-taj serves as a home for sorcerers and mystics. “We went to Kathmandu, nepal, scouted the place a few times and shot some stairs there. Charles rebuilt a huge temple in London at Longcross Studios that was precise, detailed and beautiful. We did a lot of set extensions so we recreated it digitally. We also recreated a CG view of Kathmandu from Kamar-taj that was done by Method Studios. It’s very good.”
The trailers for Doctor Strange only offer a glimpse into what audience members are going to experience when watching the movie. “We were trying to push the Marvel Cinematic Universe even further. In Guardians we started sending it to the galaxies and now there is lots of travelling across the dimensions so we’re really going into other worlds. It’s both exciting and unique as well.”
Marvel’s Doctor Strange is in cinemas from 26 October.