Over a period of 18 months, Australia’s Rising Sun Pictures (RSP) provided some 170 special effects shots for "Thor: Ragnarok," helping to make it one of the most critically and commercially successful movies of 2017. From character modeling to creature creation and set design, they helped shape Thor’s visuals from pre-production through to the final cut. RSP’s CG Supervisor, Hubert Maston, talks us through their work on the film, the challenges they faced, and the tools they used to pull it all off.
When Marvel approached us about doing work for Thor: Ragnarok, there were three main sequences they wanted our help with: a flashback sequence told from the perspective of Val, a crucial scene involving the Bifrost Bridge, and some fight scenes involving the main antagonist, Hela, played by Cate Blanchett. Each of these sequences involved some combination of environment design – whether for the Bifrost Bridge itself, or the Asgardian Palace – and creature creation (we had some 150 winged horses running around, at one point), plus digitizing one or more of the main actors. It was a lot of work, but fortunately, we had expended our character animation department prior to taking this project on.
Bringing the mythical and the imaginary to life
One of the fun things about working on a project like this is that we get to give our imaginations greater scope. After all, we’re designing things that don’t exist in real life. But we’re still constrained by the need to make things real for the audience. I tend to think about it in terms of “plausible” and “real.” We might be building things that don’t exist, but they need to look plausible, or the audience won’t give them any credit. So that’s usually our starting point.
In the case of the Bifrost Bridge, for example, there was already some visual reference to it from previous movies, and we had some idea of the direction we wanted to go with it, and then it became a matter of trying out different ideas that had some kind of real-life parallel. What if the bridge was made of ice and crystals? What if it looks more like a liquid? Or something fragile and breakable? You always start with something real, something that you can describe, and then it evolves through different iterations to an actual look. But you try to never lose that original, plausible image.
This was a very labor-intensive process. We probably went through 100 iterations of the Bifrost Bridge before we got the look we wanted.
The main sequences
The foundational work for each sequence was more or less the same. We basically recreated the environment for everything we did – be that the palace or the Bifrost – in digital form, using Maya and Mudbox for modeling and Arnold for rendering. But there’s a twist: we actually developed our own tracking and layout system, based on Maya. We would do the entirety of the layout work, including match move and camera tracking, in Maya, using our own tools, and switch to Houdini just to do lighting or effects.
Because these shots are so demanding, from a visual standpoint, we need to be involved very early in the planning stages. Take the flashback sequence, for example. Before shooting even began, we’d done a full pre-vis of the sequence, designing it in detail and passing that information on to the on-set team, so that they could create all the elements we would need to execute the sequence.
For pre-vis itself, our approach is pretty standard. We had a crude version of the assets, and rough animation, to help with look dev. But in this flashback scene, we did an interesting thing with our light rig. We had this big metal ring, with camera flashes hooked up to it, and we shot it with high-speed cameras. The end effect is of a real horse running through the set in slow motion, with a rotating light source that almost looks like the sun moving in time-lapse. The resulting look was very unique.
In post-vis, we started to design the actual assets, create wings for these flying horses, replace limbs, work on character models. We had a veritable army of CG riders going through the environment. And Hela, Cate Blanchett’s character, took a lot of work. It was mostly body replacement, which is why we used MotionBuilder for mocap. We obviously wanted to keep as much of her performance as possible, but for fight sequences and the like, we replaced her body with a digital outfit using our character pipeline.
In the end, the flashback sequence was only about 20 shots or so, but probably 90% of it was CG, so it represented a ton of work.
The next sequence, in the palace throne room, was a bit more conventional. It was shot on set, using a combination of blue screen and real props, and we just rendered the whole thing entirely digital. Most of the time, when Hela and Thor are fighting, the environment is digital; we just extracted Cate Blanchett and Chris Hemsworth out of the plate. We did the rendering in Arnold, or a combination of Arnold and Mantra, but most of the palace fight was done using Arnold – even the volumes.
The Bifrost Bridge sequence was more of the same. We replaced a bunch of bodies and inputted a handful of fully CG characters. The Bifrost itself is a combination of effects, but we gave the whole thing a 2D treatment to get its final look.
The whole thing ended up being about 170 shots, which took our team of roughly 200 people 18 months to complete. In terms of volume, that’s about a medium-sized project for us, though this one was unusual in that it involved a lot of creative design, making things from scratch, which always adds a degree of difficulty to the work. The Marvel team was very helpful in that regard, providing guidance and feedback from the get-go, and helping us really focus on storytelling and visual development.
Working in slow motion
Working in slow motion is always interesting. A lot depends on the design of the sequence, and so we spend a lot of time getting that right. We had experience in shooting the character Quicksilver from X-Men: Apocalypse, but that particular scenario – a character moving so fast that he makes everyone else look like they’re moving in slow motion – doesn’t translate into every film. So for this shot, we collaborated with The Third Floor, since they were responsible for the on-set setup, and for positioning the rigs and cranes. Once the shot itself is set up, the tricky part is getting all of the effects to look right in slow motion. Smoke, for example, has to look a particular way to look authentic.
Tools of the trade
At the moment, we’re using Maya 2017 and Arnold 5, though on Thor: Ragnarok it was Maya 2016 and Arnold 4. We used MotionBuilder to treat the mocap, especially the body mocap, and Mudbox for modeling. We have some ZBrush guys, but we use Mudbox every day, and our head of modeling is a Mudbox guy. We have our own character and rigging system based on Maya, so we made extensive use of that and plugins like Yeti to handle complex character animations, muscle simulations, grooming, and other intricate elements.
We’re pretty proud of how we’ve learned to get the most of our tools, particularly when we’re dealing with massive data loads. We evolved our own visualization technique, for example, to deal with the 150 winged horses we had to incorporate into one sequence. Using the Maya viewport, we were able to do the layout with the horses and see only the final versions at render time, so we could just move them around how we pleased to design the movements of the army.
Arnold is also great. It’s simple, it’s easy to use, and it makes sense. We love that it enables us to use scientific principles while developing a look, and we have a confidence in Arnold that, if our look dev makes sense, anything we make will look good right away – even the first version.
As far as rendering goes, we’re extremely mindful of efficiency. On this particular project, we used a render farm of about 600 nodes, and we were extremely mindful of our setup.
Finally, we use Shotgun to keep track of shots and tasks. In fact, I think Rising Sun Pictures was one of the first companies to incorporate Shotgun, years ago. All of our dailies go in there, all of the renders, everything that actually gets published – it’s all visible and accessible inside Shotgun. We use it to assign tasks and create to-do lists, or just communicate with team members, giving feedback, leaving notes – even client feedback is recorded in Shotgun. It’s our main source of information.
We keep an open pipeline and don’t like to restrict ourselves in terms of the software we use, but our front end is all done in Maya for a reason. It excels at being a hob for a lot of things, it’s an open tool that lets us work on everything from creature development to tracking – basically, everything that we need to build, we can usually get it done with Maya.
Taking pride in the work
For me, personally, the visual and storytelling aspects of my work are the most enjoyable and rewarding. A lot of the work we do is with layouts, trying to figure out how to tell the story visually, and then developing the look and feel of the picture. The technical aspects are obviously incredibly important, but they’re a means to an end, and the aim has to be telling a compelling story.
In Thor: Ragnarok, I’m particularly proud of the flashback sequence. It’s incredibly unique, has this very peculiar look you won’t find in many other movies, and it’s a key piece of the movie. I was also gratified to find, as we were creating our animation arsenal for this movie, that we were on the right track, visually. The creatures are fully digital, but they’re believable. Or Cate Blanchett’s character: nobody really questioned whether or her body was real or not, even though so much of her movement in the film was done digitally. That was very validating for us.
Hubert and the team at Rising Sun Pictures produced groundbreaking and creative work for Thor: Ragnarok using products available in the Autodesk Media & Entertainment Collection.