By Daniel Restuccio
With Sony’s Spider-Man: Homecoming getting ready to release digitally on September 26 and on 4K Ultra HD/Blu-ray, Blu-ray 3D, Blu-ray and DVD on October 17, we thought this was a great opportunity to talk about some of the film’s VFX.
Sony Imageworks has worked on every single Spider-Man movie in some capacity since the 2002 Sam Raimi version. On Spider-Man: Homecoming, Imageworks worked on mostly the “third act,” which encompasses the warehouse, hijacked plane and beach destruction scenes. This meant delivering over 500 VFX shots, created by over 30 artists (at one point this peaked at 200) and compositors, and rendering out 2K finished scenes.
All of the Imageworks artists used Dell R7910 workstations with Intel Xeon CPU E5-2620 24 cores, 64GB memory and Nvidia Quadro P5000 graphics cards. They used Cinesync for client reviews and internally they used their in-house Itview software. Rendering technology was SPI Arnold (not the commercial version) and their custom shading system. Software used was Autodesk 2015, Foundry’s Nuke X 10.0 and Side Effects Houdini 15.5. They avoided plug-ins so that their auto-vend, breaking of comps into layers for the 3D conversion process, would be as smooth as possible. Everything was rendered internally on their on-premises renderfarm. They also used the Sony “Kinect” scanning technique that allowed their artists to do performance capture on themselves and rapidly prototype ideas and generate reference.
We sat down with Sony Imageworks VFX supervisor Theo Bailek, who talks about the studio’s contribution to this latest Spidey film.
You worked on The Amazing Spider-Man in 2012 and The Amazing Spider-Man 2 in 2014. From a visual effects standpoint, what was different?
You know, not a lot. Most of the changes have been iterative improvements. We used many of the same technologies that we developed on the first few movies. How we do our city environments is a specific example of how we build off of our previous assets and techniques, leveraging off the library of buildings and props. As the machines get faster and the software more refined, it allows our artists increased iterations. This alone gave our team a big advantage over the workflows from five years earlier. As the software and pipeline here at Sony has gotten more accessible, it has allowed us to more quickly integrate new artists.
It’s a lot of very small, incremental improvements along the way. The biggest technological changes between now and the early Spider-Mans is our rendering technology. We use a more physically-accurate-based rendering incarnation of our global illumination Arnold renderer. As the shaders and rendering algorithms become more naturalistic, we’re able to conform our assets and workflows. In the end, this translates to a more realistic image out of the box.
The biggest thing on this movie was the inclusion of Spider-Man in a Marvel Universe: a different take on this film and how they wanted it to go. That would be probably the biggest difference.
Did you work directly with director Jon Watts, or did you work with production VFX supervisor Janek Sirrs in terms of the direction on the VFX?
During the shooting of the film I had the advantage of working directly with both Janek and Jon. The entire creative team pushed for open collaboration, and Janek was very supportive toward this goal. He would encourage and facilitate interaction with both the director and Tom Holland (who played Spider-Man) whenever possible. Everything moved so quick on set, often times if you waited to suggest an idea you’d lose the chance, as they would have to set up for the next scene.
The sooner Janek could get his vendor supervisors comfortable interacting, the bigger our contributions. While on set I often had the opportunity to bring our asset work and designs directly to Jon for feedback. There were times on set when we’d iterate on a design three or four times over the span of the day. Getting this type of realtime feedback was amazing. Once post work began, most of our reviews were directly with Janek.
When you had that first meeting about the tone of the movie, what was Jon’s vision? What did he want to accomplish in this movie?
Early on, it was communicated from him through Janek. It was described as, “This is sort of like a John Hughes, Ferris Bueller’s take on Spider-Man. Being a teenager he’s not meant to be fully in control of his powers or the responsibility that comes with them. This translates to not always being super-confident or proficient in his maneuvers. That was the basis of it.
Their goal was a more playful, relatable character. We accomplished this by being more conservative in our performances, of what Spider-Man was capable of doing. Yes, he has heightened abilities, but we never wanted every landing and jump to be perfect. Even superheroes have off days, especially teenage ones.
This being part of the Marvel Universe, was there a pool of common assets that all the VFX houses used?
Yes. With the Marvel movies, they’re incredibly collaborative and always use multiple vendors. We’re constantly sharing the assets. That said, there are a lot of things you just can’t share because of the different systems under the hood. Textures and models are easily exchanged, but how the textures are combined in the material and shaders… that makes them not reusable given the different renderers at companies. Character rigs are not reusable across vendors as facilities have very specific binding and animation tools.
It is typical to expect only models, textures, base joint locations and finished turntable renders for reference when sending or receiving character assets. As an example, we were able to leverage somewhat on the Avengers Tower model we received from ILM. We did supply our Toomes costume model and Spider-Man character and costume models to other vendors as well.
The scan data of Tom Holland, was it a 3D body scan of him or was there any motion capture?
Multiple sessions were done through the production process. A large volume of stunts and test footage were shot with Tom before filming that proved to be invaluable to our team. He’s incredibly athletic and can do a lot of his own stunts, so the mocap takes we came away with were often directly usable. Given that Tom could do backflips and somersaults in the air we were able to use this footage as a reference for how to instruct our animators later on down the road.
Toward the later-end of filming we did a second capture session, focusing on the shots we wanted to acquire using specific mocap performances. Then again several months later, we followed up with a third mocap session to get any new performances required as the edit solidified.
As we were trying to create a signature performance that felt like Tom Holland, we exclusively stuck to his performances whenever possible. On rare occasions when the stunt was too dangerous, a stuntman was used. Other times we resorted to using our own in-house method of performance capture using a modified Xbox Kinect system to record our own animators as they acted out performances.
In the end performance capture accounted for roughly 30% of the character animation of Spider-Man and Vulture in our shots, with the remaining 70% being completed using traditional key-framed methods.
How did you approach the fresh take on this iconic film franchise?
It was clear from our first meeting with the filmmakers that Spider-Man in this film was intended to be a more relatable and light-hearted take on the genre. Yes, we wanted to take the characters and their stories seriously, but not at the expense of having fun with Peter Parker along the way.
For us that meant that despite Spider-Man’s enhanced abilities, how we displayed those abilities on screen needed to always feel grounded in realism. If we faltered on this goal, we ran the risk of eroding the sense of peril and therefore any empathy toward the characters.
When you’re animating a superhero it’s not easy to keep the action relatable. When your characters possess abilities that you never see in the real world, it’s a very thin line between something that looks amazing and something that is amazingly silly and unrealistic. Over-extend the performances and you blow the illusion. Given that Peter Parker is a teenager and he’s coming to grips with the responsibilities and limits of his abilities, we really tried to key into the performances from Tom Holland for guidance.
The first tool at our disposal and the most direct representation of Tom as Spider-Man was, of course, motion capture of his performances. On three separate occasions we recorded Tom running through stunts and other generic motions. For the more dangerous stunts, wires and a stuntman were employed as we pushed the limit of what could be recorded. Even though the cables allowed us to record huge leaps, you couldn’t easily disguise the augmented feel to the actor’s weight and motion. Even so, every session provided us with amazing reference.
Though a bulk of the shots were keyframed, it was always informed by reference. We looked at everything that was remotely relevant for inspiration. For example, we have a scene in the warehouse where the Vulture’s wings are racing toward you as Spider-Man leaps into the air stepping on the top of the wings before flipping to avoid the attack. We found this amazing reference of people who leap over cars racing in excess of 70mph. It’s absurdly dangerous and hard to justify why someone would attempt a stunt like that, and yet it was the perfect for inspiration for our shot.
In trying to keep the performances grounded and stay true to the goals of the filmmakers, we also found it was always better to err on the side of simplicity when possible. Typically, when animating a character, you look for opportunities to create strong silhouettes so the actions read clearly, but we tended to ignore these rules in favor of keeping everything dirty and with an unscripted feel. We let his legs cross over and knees knock together. Our animation supervisor, Richard Smith, pushed our team to follow the guidelines of “economy of motion.” If Spider-Man needed to get from point A to B he’d take the shortest route — there’s not time to strike an iconic pose in-between!
Let’s talk a little bit about the third act. You had previsualizations from The Third Floor?
Right. All three of the main sequences we worked on in the third act had extensive previs completed before filming began. Janek worked extremely closely with The Third Floor and the director throughout the entire process of the film. In addition, Imageworks was tapped to help come up with ideas and takes. From early on it was a very collaborative effort on the part of the whole production.
The previs for the warehouse sequence was immensely helpful in the planning of the shoot. Given we were filming on location and the VFX shots would largely rely on carefully choreographed plate photography and practical effects, everything had to be planned ahead of time. In the end, the previs for that sequence resembled the final shots in most cases.
The digital performances of our CG Spider-Man varied at times, but the pacing and spirit remained true to the previs. As our plane battle sequence was almost entirely CG, the previs stage was more of an ongoing process for this section. Given that we weren’t locked into plates for the action, the filmmakers were free to iterate and refine ideas well past the time of filming. In addition to The Third Floor’s previs, Imageworks’ internal animation team also contributed heavily to the ideas that eventually formed the sequence.
For the beach battle, we had a mix of plate and all-CG shots. Here the previs was invaluable once again in informing the shoot and subsequent reshoots later on. As there were several all-CG beats to the fight, we again had sections where we continued to refine and experiment till late into post. As with the plane battle, Imageworks’ internal team contributed extensively to pre and postvis of this sequence.
The one scene, you mentioned — the fight in the warehouse — in the production notes, it talks about that scene being inspired by an actual scene from the comic The Amazing Spider-Man #33.
Yes, in our warehouse sequence there are a series of shots that are directly inspired by the comic book’s cells. Different circumstances in the the comic and our sequence lead to Spider-Man being trapped under debris. However, Tom’s performance and the camera angles that were shot play homage to the comic as he escapes. As a side note, many of those shots were added later in the production and filmed as reshoots.
What sort of CG enhancements did you bring to that scene?
For the warehouse sequence, we added digital Spider-Man, Vulture wings, CG destruction, enhanced any practical effects, and extended or repaired the plate as needed.The columns that the Vulture wings slice through as it circles Spider-Man were practically destroyed with small denoted charges. These explosives were rigged within cement that encased the actual warehouses steel girder columns. They had fans on set that were used to help mimic interaction from the turbulence that would be present from a flying wingsuit powered by turbines. These practical effects were immensely helpful for our effects artists as they provided the best-possible in-camera reference. We kept much of what was filmed, adding our fully reactive FX on top to help tie it into the motion of our CG wings.
There’s quite a bit of destruction when the Vulture wings blast through walls as well. For those shots we relied entirely on CG rigid body dynamic simulations for the CG effects, as filming it would have been prohibitive and unreliable. Though most of the shots in this sequence had photographed plates, there were still a few that required the background to be generated in CG. One shot in particular, with Spider-Man sliding back and rising up, stands out in particular. As the shot was conceived later in the production, there was no footage for us to use as our main plate. We did however have many tiles shot of the environment, which we were able to use to quickly reconstruct the entire set in CG.
I was particularly proud of our team for their work on the warehouse sequence. The quality of our CG performances and the look of the rendering is difficult to discern from the live action. Even the rare all-CG shots blended seamlessly between scenes.
When you were looking at that ending plane scene, what sort of challenges were there?
Since over 90 shots within the plane sequence were entirely CG we faced many challenges, for sure. With such a large number of shots without the typical constraints that practical plates impose, we knew a turnkey pipeline was needed. There just wouldn’t be time to have custom workflows for each shot type. This was something Janek, our client-side VFX supervisor, stressed from the onset, “show early, show often and be prepared to change constantly!”
To accomplish this, a balance of 3D and 2D techniques were developed to make the shot production as flexible as possible. Using our compositing software Nuke’s 3D abilities we were able to offload significant portions of the shot production into the compositor’s hands. For example: the city ground plane you see through the clouds, the projections of the imagery on the plane’s cloaking LED’s and the damaged flickering LED’s were all techniques done in the composite.
A unique challenge to the sequence that stands out is definitely the cloaking. Making an invisible jet was only half of the equation. The LEDs that made up the basis for the effect also needed to be able to illuminate our characters. This was true for wide and extreme close-up shots. We’re talking about millions of tiny light sources, which is a particularly expensive rendering problem to tackle. Mix in the fact that the design of these flashing light sources is highly subjective and thus prone to needing many revisions to get the look right.
Painting control texture maps for the location of these LEDs wouldn’t be feasible for the detail needed on our extreme close-up shots. Modeling them in would have been prohibitive as well, resulting in excessive geometric complexity. Instead, using Houdini, our effects software, we built algorithms to automate the distribution of point clouds of data to intelligently represent each LED position. This technique could be reprocessed as necessary without incurring the large amounts of time a texture or model solution would have required. As the plane base model often needed adjustments to accommodate design or performance changes, this was a real factor. The point cloud data was then used by our rendering software to instance geometric approximations of inset LED compartments on the surface.
Interestingly, this was a technique we adopted from rendering technology we use to create room interiors for our CG city buildings. When rendering large CG buildings we can’t afford to model the hundreds and sometimes thousands of rooms you see through the office windows. Instead of modeling the complex geometry you see through the windows, we procedurally generate small inset boxes for each window that have randomized pictures of different rooms. This is the same underlying technology we used to create the millions of highly detailed LEDs on our plane.
First our lighters supplied base renders to our compositors to work with inside of Nuke. The compositors quickly animated flashing damage to the LEDs by projecting animated imagery on the plane using Nuke’s 3D capabilities. Once we got buyoff on the animation of the imagery we’d pass this work back to the lighters as 2D layers that could be used as texture maps for our LED lights in the renderer. These images would instruct each LED when it was on and what color it needed to be. This back and forth technique allowed us to more rapidly iterate on the look of the LEDs in 2D before committing and submitting final 3D renders that would have all of the expensive interactive lighting.
Is that a proprietary system?
Yes, this is a shading system that was actually developed for our earlier Spider-Man films back when we used RenderMan. It has since been ported to work in our proprietary version of Arnold, our current renderer.