Joss Whedon’s Avengers: Age of Ultron adds a glorious and enormous cog to the ever-evolving juggernaut that is the Marvel Universe. The success of which is due, in no small part, to not only those chosen as on-screen talent, but also the sorcerers behind the scenes. 

When it came to this sorcery, Marvel relied on the movie making wizards from Industrial Light & Magic to deliver the goods. And, ILM turned to their VFX veteran, Ben Snow to supervise some of the most complex special effects and character work ever captured on film.

Ben Snow has been nominated four times at the Academy Awards, and is renowned for his sterling work on some of the biggest projects in modern movie making history, such as Iron Man (2008), Iron Man 2 (2010) and King Kong (2005). Snow started his film-making passion as a young boy on an Australian farm. Armed with a Super 8 camera, and a cohort of willing friends and family, he conjured many amateur epics.

It was around this time that he came across an article about The Empire Strikes Back in “American Cinematographer” by the effects director of photography, Dennis Muren. Yes, that Dennis Muren! Fast forward a couple of decades, and after years of hard work and honing his craft, Snow was mentored by Muren on his first film as VFX supervisor. It was a movie you may have heard about: Star Wars: Episode II – The Attack of the Clones (2002).

When you delve into just how big Avengers: Age of Ultron is, you quickly realise why somebody of Snow’s experience and caliber was required. He and his team at ILM worked on a “little over 800 final shots” alone. Snow went on to explain that they did “most of the big acting shots, particularly those involving Ultron Prime and Hulk, a lot of the open sequence, and most of the end of the movie from the lift off of Sokovia and the final battle. The film was giant, and had something like 3000 shots, crazy big! More than any film I’ve been involved in.” Let us not forget that Snow has worked on a couple of Star Wars movies and King Kong, so when he says “crazy big”, you gotta believe this thing is jaw-droppingly huge!

They began the project in December 2013, when Snow was still working on Noah. That early in the piece there were some “previs and concept art and rough concepts on Ultron.” It was around this time that they started building the Hulkbuster, which is the heavy-duty exo-frame used to combat the bewitched Hulk. “It was dream to work on,” exclaimed Snow. “It was an absolutely beautiful design from Marvel’s Viz Dev department. But when you are building something that needs to move around you need a bit of redesign, so we got to embellish the design a little bit. It was just one of the most fun characters we built. It’s just so cool – basically Iron Man in an Iron Man suit!”

ILM also built the highly detailed Ultron Prime, which according to Snow was “probably the most complex hard-surface hero model we’ve had to do in terms of the rig. It had something like 2000 parts, with 600 in the face alone, to be able to make him articulate and capture the subtlety of what we were getting from James Spader’s performance.”

Spader was indeed an inspired piece of casting. He is a wonderfully nuanced actor, capable of going from insecure to menacing with just a subtle change of expression or tone in his voice. Capturing his exemplary performance in a hard surface model, understandably gave the ILM team some sleepless nights.

“Ultron was pretty elaborate,” Snow said. “We were really worried about him, and he took a long time to rig. It was an evolutionary process where the rigger would work with the animator once we finally got a rig that was working. The problem was with his face; with the articulation we were seeing with James Spader’s performance, you really need the capabilities you have in a Davy Jones type creature. But Ultron is made of hard metal, so we couldn’t squash and stretch like you could with Davy Jones.” In order to capture the performance, the team devised an ingenious network of sliding plates, which more than ably mimicked Spader’s outstanding performance. “The animators did a great job of channelling what James was doing on set and building on that to create this CG villain.”

More sleepless nights were had when Snow and his team came across “a sequence where Ultron engineers it so a whole chunk of an Eastern European city lifts off from the ground on these giant anti-gravity devices, which have been backwards engineered from the Leviathan from the first Avenger’s film.”

To start with, the city does not exist. “We filmed in several locations in Italy and the UK to cover the ground portions that happened in the street, so that gave us a lot of raw material for the design. But it ended up being one of our largest digital matte painting creations. We had this 2 kilometer expanse of city that we had to build as a digital matte painting, plus the ground that it is sitting on top of, plus the engines that are driving it, complete with the pipes and the infrastructure under the ground with bits of earth falling off it. To get it right we studied landslide footage, building demolition and earthquake footage.”

“So, we had to not only build it as digital matte asset but also lift it out of the ground with the edge of it breaking away and the buildings crumbling like they were in an earthquake. It became a very elaborate process. Our traditional pipeline had been aimed more at single building destruction, like at the end of the Transformers movie. Here we were destroying whole sections of the city. So, we basically built on our pipeline so we could turn a digital matte asset into a generalist asset made in 3DS Max, then we took it through our rigid simulation system and sent it back for rendering in the generalist pipeline.”

Snow is understandably incredibly proud of this extraordinary example of destruction mastery, but he loved the character work the most. And you do not get a bigger character than the Hulk! Together with Christopher Townsend, Marvel’s Visual Effects Supervisor, Snow and his team discussed how they could rebuild Hulk to meet the challenges of the movie.

“Hulk has to do a lot more acting in this film compared to the last, and he’s got some quite emotional scenes,” Snow explained.  They enlisted Mark Ruffalo’s help, and revisited Hulk’s facial shape to make sure it more exactly matched Ruffalo’s facial structure. Then they “revamped his underlying muscle system completely. We changed the model completely so we could get a lot more detail through the geometry rather than just displacement and bump mapping. “

They took a lot of the detail from the original model and put it “down onto the muscle level so the skin acted more as a wrapper on the muscle sim. We really had them drive everything. There were three layers of flesh and then a fascia of the skin riding over the flesh to impart much more realism to the character.”

In order to impart even more realism, they had Rob de Groot on set. The body-building stuntman is an imposing figure, and they had him “doing a whole series of exercises that the model and creature team came up with, so we could see how his muscles tensed and stretched. We combined that observation with hard science and medical information about how muscles reacted.”

All that hard work and attention to detail has clearly paid off. Avengers: Age of Ultron is a visual feast, thanks to Snow, his team at ILM, and the 20 or so other VFX studios involved. And, if you are anything like me, you’re going to see it a bunch of times!

Related links
Avengers: Age of Ultron
Ben Snow IMDb
Industrial Light & Magic