Art of VFX: The Revenant, Cinesite VFX Supe Nicolas Chevallier Interviewed

Nicolas Chevalier began his career in visual effects in 2001 at Buf Compagnie, he worked on many films such as BATMAN BEGINS, SILENT HILL or THOR. He moved two years in London at BlueBolt and then joined MPC in Montreal in 2014 for X-MEN: DAYS OF FUTURE PAST. In 2015, he comes to Cinesite to take care of the effects of THE REVENANT.

What is your background?

I joined Cinesite’s Montreal visual effects team as VFX Supervisor in March 2015. I moved with my family to Montreal in 2013 to be Compositing Supervisor on the extensive visual effects feature INTO THE WOODS at MPC. My other credits while at MPC included EXODUS: GODS AND KINGS and X-MEN: DAYS OF FUTURE PAST.

Originally from France, (a Supinfocom graduate) I established my visual effects career at BUF Compagnie in 2001; where I remained for almost 10 years. My credits as a CG artist include THE MATRIX REVOLUTIONS, THE MATRIX RELOADED and FINDING NEVERLAND. I subsequently became a CG Supervisor on BATMAN BEGINS and SILENT HILL then a VFX Supervisor. While at BUF, I supervised the effects on Marvel’s THOR.

I also spent two years in London working at BlueBolt, as a VFX Supervisor. During this time I was part of the team working on SNOW WHITE AND THE HUNTSMAN, and MANDELA: LONG WALK TO FREEDOM.

How did you and Cinesite get involved on this show?

We originally did a stitch test back in February 2015 to assemble multiple takes and thus create a single shot. The test was successful and as a result Cinesite was initially awarded a niche body of work. We began with about 7 shots including complex stitches and set extensions but as the cut of the film progressed and our relationship with Rich McBride, the studio VFX Supervisor and Ivy Agregan the VFX Producer grew stronger our the shot count increased to 138 shots which is approximately 38 minutes of the movie.

How was your collaboration with director Alejandro G. Iñárritu and VFX Supervisor Rich McBride?

I think we had a very collaborative relationship with Richard, he was always very open to our suggestions and input and personally I really enjoyed working with him. He would use various methods to pass on feedback and give us shot briefings. Depending on complexity it could be a written note or phone calls.

Following Cinesite being awarded the end battle sequence between Fitzgerald and Glass, my producer Alain Lalanne and I flew to LA to meet Alejandro. This meeting was great because it gave us a true sense of Alejandro ‘s vision and provided us with an opportunity to discuss methodology for the shoot with DP Emanuel “Chivo” Lubezki and the wider VFX team.

Richard had a very precise idea of what Alejandro was after and could give us a good steer before submitting anything for reviews, this meant we knew when we’d show work to Alejandro it would be what he expected. This meant there was a lot less back-and-forth in terms of getting shots finalled, which was really important with the volume of shots and the time we had.

What was their approach about the visual effects?

It’s been widely reported that the shoot was challenging. The locations were often inaccessible, the weather unpredictable and lighting conditions varied throughout the shoot, nevertheless the whole team worked together to shoot some beautiful images for VFX. The main thing was to make sure the effects were grounded in a reality that meant even adding imperfections and randomness to every single element we generated.

Congratulations for making the Oscar shortlist for visual effects. What is it about the visual effects do you think resulted in the Academy members responding so well to them?

Thank you, it’s a fantastic acknowledgment of Cinesite’s extensive work across the production. I think the majority of audiences, including Academy members are really interested in visual effects which strive for realism and serve the story rather than drive it. This year’s nominations are reflective this.

Can you describe one of your day’s during the post?

We tended to have a routine of CG dailies in the morning (matchmove, FX, assets, environment, lighting) followed by compositing in the afternoon. This allowed us to make any final tweaks towards the end of the day and prepare the package to send to the client for review. It was vital for me to check all the work at every step of the delivery. Editorial was completely in sync as well and were and involved at every step to ensure we had the right color, timing and framing. Sometimes we would break this routine to have a few cineSync calls with the VFX team on the production side this was often for a direct briefing. All the feedback, either from Richard or Alejandro was very precise and clear.

What are the sequences made by Cinesite?

This is a difficult question. Usually on a show, a vendor is awarded for a sequence with specific assets, builds or look. Due to the nature of the film THE REVENANT saw us working on shots, which are transitional across the feature. Overall we delivered 138 VFX shots comprising 38 minutes of film. The range of invisible effects included digital matte paintings and set extensions, fluid and particle FX simulations, character animation, lighting, cg trees, cleaning and compositing. Our main task, working across the London, Montreal and Vancouver teams, was to create the fluid transitions between shots, eliminating cuts and enhancing the experiential aspect of the drama.

One continuous sequence, we achieved, was the end battle, which is about 50 shots. This sequence was split between the two sites for timing reasons. The London team did the snow animation when Glass & Fitz are fighting as well as adding the knife and axe throughout a continuous shot sliced in multiples takes. These takes had to be combined together to allow the audience to be seamlessly following the fighters. The Montreal team completed the complex stitches, the sky replacements, set extensions, and snow additions which feature throughout the scene.

Alejandro G. Iñárritu is known for long continuous shots. How did you approach and created these shots?

This is something that is definitely part of Alejandro’s signature cinematography. The challenge on each individual shot was to find the right pace for the two takes to ensure a seamless blend. Once this optimum point had been found in compositing, we went back through the different departments to create retime camera according the timing, full CG environment, and geometry to project on. It wasn’t until the final compositing days, that we really knew whether or not our transitions has seamlessly blended or whether we would have to review and select alternative timing!

In contrast with all the other productions I have worked on, the editorial was not locked until just before the delivery. Harry Yoon, the client VFX editor, helped us a lot by creating mock-ups to start with. Considering this first draft as a guide, we adjusted the timing of the transition sometime with just a few frames, but in other cases we trimmed the shot up to 50 frames. He was constantly adjusting the edit to make sure we had the best chances to achieve an invisible transition.

Which continuous shots were the most complicated to do and why?

All the stitches presented their own challenge. However there is one stitch in particular that springs to mind. When Leo is hiking from the river to the top of the hill discovering a herd of buffalos. The first part, which we will call the A plate, was tremendously long and just before the sun rises. The B plate captured Leo reaching the brow of the hill before the camera pans across the plateau, discovering the buffalos. The sun in B plate was already bleeding through the clouds. Because of technical constraint and lighting conditions the two plates were different in terms of perspective, grading and lighting. First of all we needed to find a way to bring the two plates in the same world by delicately tuning the grade of A plate. Then we had to find the optimum spot between those and finally we needed to select what we needed to build in 3D to remove yourself from the A plate camera to connect to the B plate camera. Once this is done, we added 3D branches in foreground to cover the connection. Alejandro’s wanted the audience to see Leo through the foreground tree. To achieve this we selected part of Leo’s animation earlier in the shot and added him behind the tree. The challenge with stitches was treating each shot as a stand-alone puzzle because there were multiples options to succeed every time.

What was the main challenge with these continuous shots?

Finding the optimum point between plates to ensure a seamless blend.

How did you enhance the various landscapes and skies?

Chivo is a true artist with a camera shooting using only natural light in locations with minimal daylight hours but sometimes the weather was not very cooperative for him. This led to us creating a handful of sky replacements using amazing stills photography and adding it to the cinematography. We built the environment when needed to add reflection to increase the realism. Set extension, crew cleanup and snow addition was also part of our remit.

The final battle is really intense and bloody. Can you tell us more about your work on it?

The end battle sequence is something we’re all particularly proud of. The scene has been received well by cinema audiences because it delivers the immersion and immediacy of the nail biting confrontation between Glass & Fitzgerald. For this sequence we added weaponry for the two fighters. Fitz’ knife was built in three different variations (Rusty /clean, snowy and covered with blood), to match the progression of the fight scene.

This sequence had been shot over multiples days and consequently with different light & weather conditions. To help continuity, we added failing snow and lots of rocks around the battle to give it an added sense of isolation.

How did you create the various FX elements?

Most of the work was created using Maya even and a few with Houdini. Our FX simulations are peppered throughout multiple shots to maintain continuity and support the story. Snow simulations were composited with deep renders to allow us to embed the characters. Most of the time, we constructed a simple 3D scene to get the correct scale and when we needed the characters they were roto-animated to use as collider in the different simulations.

How did you split the work between the Cinesite offices?

In order to achieve high-end quality work in the time frame we had, we decided to split sequences between our two sites. Montreal is ideally placed to review the work from London, we used an in-house RV tool to play the shots simultaneously between sites, and publish comments in ftrack to track easily the progression for each individual shot.

Was there a shot or a sequence that prevented you from sleep?

All the sequences were challenging but not to this point. We had great teams working in every department; this coupled with a fantastic relationship with the client enabled us to prevent any issues from occurring in advance.

What do you keep from this experience?

Don’t hesitate to start from scratch again and again!

How long have you worked on this show?

I worked on THE REVENANT for approximately 6 months.

What was the size of your team?

We had a total of 86 Cinesite artists working on THE REVENANT.

What is your next project?

Cinesite currently has several shows in production including NOW YOU SEE ME: THE SECOND ACT which I’m supervising but also INDEPENDENCE DAY RESURGENCE and FANTASTIC BEASTS.

What are the four movies that gave you the passion for cinema?

I’m afraid they are a little predictable but when I was younger it was the original STAR WARS trilogy, as it was for a lot of people of my age but I also have to mention TRON and GHOSTBUSTERS.

A big thanks for your time.

Art of VFX, 21 January, 2016