Warning: This article contains some details from Doctor Strange that could distract from the overall experience if you have not yet seen the film.

From the very first scene, Doctor Strange gave us a world that twisted, turned, fell apart, and fell back together. Yet somehow, there was still a realistic quality to this world, even while we watched it move in very unrealistic ways. There was a cinematic quality that went beyond the action of a green-screen, which was carefully crafted by designers, previs, and visual effects artists.

Visual effects supervisor Stephane Ceretti explained to Cartoon Brew that the chase scene through New York was intended to feel like we were in the real New York City, even though some pretty amazing things were happening.

“Even with all those magic powers,” said Ceretti, “we still used elements from the world that are tangible and that the audience could relate to, so that it feels more real in a way. We made sure that the texture of the material that these buildings were made of was really real, even though they behave in a very different manner. At the end of that sequence we go completely crazy, I mean, there’s no more New York, it’s all deconstructed. It’s a gigantic kaleidoscope, but I think people will buy it because we will have taken them from the real New York to the crazy New York in a pace that is okay for them to accept.”

If the thought of a world through a kaleidoscope makes you think of M.C. Escher drawings, you aren’t alone. Taking the textures and realism of New York and making them into the Mirror World included a bit of inspiration from the well-known artist.

“The spec was to do something no one in cinema had seen before,” said Third Floor previs and postvis supervisor Faraz Hameed. “The designs themselves started with Escher references and from there it was a matter of how to push the boundaries of visual storytelling.”

“A phrase we used a lot was how could we ‘plus it’,” added Hameed. “That meant taking a first pass at an idea, reviewing it, and finding a way to not just to tell the story, but to give you goosebumps when seeing it on the big screen. We really wanted to tease and surprise the audience, which meant trying a usual but still cinematic camera and adding unexpected moves in the transformations that the viewer could still properly follow.”

The development of these views required more than imagination. Real-world data was used to create the imagery that moved on screen.

During the principal photography in New York, ILM had also installed a team in the city to shoot background plates, LIDAR scans, and photogrammetry elements from several vantage points and locations. Texture references for everything from taxis to building windows were also acquired. This would all then be used in the visual effects process either as real backgrounds or as the basis for cg buildings.

In particular, Fields utilized survey data available for New York along with some early mocked-up shots to plan required helicopter plates – these were filmed with the aid of ILM techvis on an iPad in a heads-up display (HUD) style that the chopper pilot could reference while flying. Fields was also instrumental in crafting an entire ‘virtual background’ of the city, devising a 360-degree camera rig made of GoPros to shoot it with.

This sort of technology is common when you are talking about civil engineering plans, but not so much when filming major motion pictures. It’s incredible to see the lengths that the team went to to make those scenes so realistic. In fact, technology is changing so fast that, even though the movie was just released, it would be even easier to film, today.

“Now it’s pretty easy to get these 360-camera rigs,” said Fields, “but at the time when we first started exploring this there really wasn’t anything out there. So what we did was, we scanned in the GoPros and then we designed a camera rig. We went through multiple iterations and then we 3D printed them, and we did a few fit tests at ILM in San Francisco before going to New York, and we took it out on set. We would put it out on a special rail and hang it say over the ledge of the World Trade Center. This gave us two things; a moving version of a virtual background and a way to visualize the city in 360 degrees, which was done with a vr headset.”

With all of this realistic data, the movement was made more realistic with actual research into the topography of the city. This realism wasn’t lost on viewers. It was hard not to notice the cars dropping off the streets in a very realistic manner.

“There’ll be a moment where the street is seemingly sliced off, but a car happens to move across that slice,” said Bluff. “So a car happens to just erode away as it moves and disappears, in theory reappearing somewhere else in the city. The idea of being able to play with those sorts of ideas was very unique, and challenged the artists and gave them a huge sense of ownership over what we could do.”

Solid objects moving in new ways is one area, but moving cars, and even people, are another. One scene, in particular, required more than just buildings to move around.

“We started by forming this long tube that Doctor Strange is sliding down, but we also wanted to introduce a lot of jeopardy and show that there’s some passengers in the train and they’re unaware that it’s happening because it’s in another dimension,” said Fields. “We actually did a photo shoot here at ILM just for that specific shot where we went and got 44 people from production and marketing [departments] and did photogrammetry where we would shoot 360-degree photos around each individual person and then we reconstructed that geometry to have as background photo real digi-doubles that we could just rapidly generate.”

That tube shot perhaps epitomises the overall approach to the whole sequence. While certainly a huge amount of computer generated imagery was involved, it also began from actual photography, as Ceretti noted. “That’s the idea behind everything in the film – trying to shoot stuff that is real and then push it and distort it and make it something different, but at least you start from the real thing.”

In the end, Industrial Light & Magic did incredible work on Doctor Strange, raising the bar for the future of visual effects. How do you feel about the realism that was put into the final product? Let us know in the comments!

Source: Cartoon Brew