Mr. X, The Fourth Musketeer
Trey Harrell, the Lighting Supervisor at Mr. X and Look Development leader for 3M, calls working on The Three Musketeers “a quite unique and challenging project.”
“In addition to the usual invisible effects, such as set extensions, digital doubles and rig removals, we also had to create an enormous amount of 17th century Paris as well as two incredibly detailed airships and a model of Notre Dame that was period accurate to the centimeter.” He adds that the biggest challenge of all for Mr. X was making sure their details would hold up under any situation. “Imagine if we got revised direction and the camera was suddenly a few centimeters off of one of the ship’s keels? It happened—you can see a couple of bolts and rivets that were ‘stripped’ when the ship was ‘built’—but we were prepared.”
Mr. X has had an ongoing relationship with Paul W. S. Anderson, the film’s director, as well as the producers at Constantin Film and Impact Pictures. As a result, they were involved with planning and concept work at a very early stage in the film’s creation. Their animation crew, led by Jason Edwardh, worked through several key sequences as pre-viz. Dennis Berardi was the on-set VFX Supervisor for the entire shoot, and Chris MacLean’s assets crew sent out teams to take ultra-high-resolution reference and texture photos of Notre Dame as well as the Tower of London complex.
Lighting / Rendering Pipeline
Trey Harrell began working on The Three Musketeers 3D immediately after wrapping up another difficult project, Tron: Legacy. Unfortunately, very little of his work on Tron could be used to assist with his new assignment. “We had recently migrated to a Maya/V-Ray pipeline in the Assets and Lighting departments, but Tron was an extremely stylized show,” recalls Trey. “Very little of our lighting and shading approach on Tron could be translated to real-world objects, locations and characters, so we rebuilt our lighting, texturing and shading toolset almost entirely during production for The Thing and Three Musketeers.”
“To that end, we had to develop a new calibrated material template library for our modelers and texture artists to use, as well as a variety of calibrated light rigs that were used during look development,” Trey continues. “We were also one of the first studios in the world to adopt Mari into our pipeline, which proved crucial due to the enormous texture resolution requirements on many of our assets.” Just the balloon on Buckingham’s airship, for example, was comprised of 64 4k uv-based texture tiles—times five or six, depending on the necessary texture channels for a given shader. The complete Buckingham airship was approximately 48 million polygons even before being displaced and subdivided! In the film’s final shot, Trey and his team had to render about 48 Buckingham airships all at once—but more on that in a bit.
The enormous texture load presented other challenges, too. RAM overhead was one, especially given the extremely fine level of detail in the models. Network I/O was another: Mr. X developed a huge array of texture management tools so that artists could generate a variety of alternate resolutions and swap on the fly while lighting.
“Our new system proved quite efficient: most look development has, by now, actually moved to the modeling and texturing stage of asset creation, allowing our texturing artists to get the look of an asset 90% of the way (or more) towards approval without the need for dedicated shader or look development TDs in most cases,” Trey says. “Because we were using calibrated look development environments—one was a re-creation of the light stage that our characters were photographed and scanned on—we were able to develop and tune our assets extremely quickly.” During their daily work sessions, Mr. X would compare their built assets side-by-side with the set photography reference. Digital doubles had to be indistinguishable from the actors from head to waist to be approved—and fairly often they were used much, much closer than that, or originally intended. “Our D’Artagnian and Constance digidoubles, in particular,” Trey notes, “had instances where we handed off between the actor and CG head to toe mid-shot with nothing to obscure the transition.”
From a lighting perspective, The Three Musketeers was the first project where Mr. X found it practical to use global illumination (GI) to speed render time and conserve RAM. “We had experimented a bit on Tron utilizing V-Ray’s light cache to accelerate glossy calculations, and that gave us the confidence to develop several GI workflows, which depended on conditions in a given shot,” explains Trey. “In general, we used brute force GI for the first one to three bounces of light on almost every shot, then switched over to an approximated light cache for secondary bounces beyond that point.”
Trey continues: “Some shots—like our hero Paris buildings—allowed us to get away with using a single frozen GI map for the entire sequence, but for the most part, we rendered GI in-line with each frame.”
To start the lighting process, Trey Harrell and Ayo Burgess, Mr. X’s lighting leads, would determine the overall look and feel of each sequence in the film. After getting tonal and approach approval on early versions of the shots, they would propagate the base lighting rig out to the rest of the team as a starting point for each sequence.
“It was apparent early on that we wanted to use photorealism as a basis for our look, but the show’s aesthetic dictated a slight sylization to mesh with the more fantastical and art-directed elements,” Trey recalls. “We finally settled on a somewhat ‘magical realism’ look for the big airship and Paris aerial shots, while relying on very physically-based realistic lighting techniques for other more invisible sequences.” To get a good base fill and color temperature, his team would create scene-specific HDRI maps. Then, says Trey, “we’d begin to light the shots very much like a DOP would approach lighting on-set.” They also had pre-rigged lighting assets, such as virtual Kino-Flos or 2k lamps, which lighting artists could drop into their scenes. The lights would interact realistically with their calibrated surfaces, with HDRI reflections of real lighting fixtures.
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