TRON LEGACY: Charlie Iturriaga – VFX Supervisor – Ollin Studio

After working several years in Mexico and Latin America, Charlie Iturriaga and Ollin Studio began a long collaboration with David Fincher working on ZODIAC, THE CURIOUS CASE OF BENJAMIN BUTTON and THE SOCIAL NETWORK. At their credits, there are also the visual effects of THE SPIRIT, LET ME IN and THE LAST AIRBENDER.

What is your background?
I studied Electronics Engineering, but dedicated most of my time studing film and working in productions for commercials and features. After a couple of years working in the local (Mexico and Latin America) industry, I started working for Hollywood features, starting with David Fincher’s ZODIAC movie.

How was the collaboration with Joseph Kosinski and Eric Barba?
During months we were working together in reviews almost every day. I had dailies review of the work I was supervising with Eric first thing in the morning (9am) and around noon. Those reviews decided the changes and look of our work, and helped get an idea of the overall design of the movie, as Eric had in his brain the movie from beginning to the end. On those reviews the materials was picked up and shown to Joe, weather to be discussed or to have a final proposal and continue with the work. We had meetings with Joe at the beginning of the production twice a week, and at some point we started having meetings almost every day, including weekends.

How did Ollin Studio got involved on this movie?
Ollin created around 260 shots in the movie, including both Stereo shots and Flat shots. We were the second biggest vendor outside Digital Domain.

What sequences did you do?
Armory (CG Environments and suit effect), Sam’s Apartment (Digial Matte Paint), Black Guard Fight (CG Environment/Set extension, Suit/Disc enhancements and fight effects), End of line Club (Set extension and environment design, Privacy screen and stairs effect of Zeus), Ending LA (Digital Matte paintings and Flare effects), Flynns Arcade (Set extensions and environments), Private room (Suit enhancements, privacy screen and Stereoscopic fixes).

What assets have you received from production?
Depending on the sequence, different kind of assets where delivered. The first ones where obviously the plates, which included 2 eyes and a QT reference of the editorial timing.
-Concept art where delivered as high res paintings by Production’s Art’s department.
-Shared geometry where delivered if it was created by another vendor (in cases where we have a sequence split between two studios).
-Look up tables and color references were sent back and forth between Ollin and Production/Digital Domain to make sure we were in the same color space and look.
-Scripts for specific effects shared through the movie, like glows or flares that were previously approved by director.

Does the director gave you references in particular?
During our numerous hours of screenings and meetings checking the shots, several references where called. One that I specially remember is when we were discussing and designing the « transition » to the tron world, which was not specifically designed or visualized. Joe created an effect in After Effects which involved some points flying to the screen, and he handled that directly to me as a start reference of the shot. He wanted to step away from the original effect where Flynn traveled to the computer and create something a little bit more in first person and a little like WIZARD OF OZ in the sense of a change that is more to the audience than to the character. After going back and forth, the effect ended up being pretty close to his original concept, just with a stereo version and proper finishing.

What was the actual size of the set?
There were different sizes…
Armory: around 15 meters by 38 meters
End of line Club: 30 meters by 30 meters approx.. .
Really huge.

How did you create the shots of Flynn arcade building?
The shot was re-created using a combination 2d matte paint and CG created elements. The 2D matte paints where the further back element, they were based on a couple of stills from primary photography and assembled using Adobe Photoshop, then mapped on a plane and attached to a scene that was 3D tracked with the original plate. Cameras were tracked with PFTrack and shared between Maya/renderman and Nuke 3D space depending on the element.

The High res (foreground) elements, and mid res (mid-distance elements) where built in Maya as 3D geometry, using photographic references of places that Production scouted and picked as the proper sourroundings of Flynns arcade. Once the geometry was created textures where applied using the same reference photographs and mapped using deep paint software. The original photographs where taken with a Canon 5D m2 in Raw and stitched in different resolutions depending on the distance from camera.

Once geometry was modeled, shading and lighting started using Renderman and a combination of Image based lighting and specific lighting for the scene. We added subtleties as grass, garbage and different elements in the floor using procedural particles and replacing them with geometry for adding randomness to the look of the street.

One funny fact is that you can see in the wide shot an Original Tron poster on the right side of the street, as well as a graffiti of the comp artist « Bto » in the wall.

Did you do something on the light suits?
Most of the light suits needed some enhancement, mainly in the falloff of the glow and consistency across the movie. It was great to have a real lightsource during the movie, as the characters interacted with the light and gave a much natural and estetic look in the movie. The cons where that for making them actually expose, most of the apertures on camera where really open, giving a soft defocus on backgrounds and edges of the characters when against blue screen, which gave a hard time on final compositing.

At some point during the post productin, Joe wanted to give a subtle flicker on all the suits, that mean that all suits needs to get a post process of a filer in nuke which gave he noisy look. Also, some parts of the suits turned off during takes, which needed to be rotoscoped and lit up again.

Some times suits were turned off for several reasons. One funny example is during the Black Guard fight, Sam did some of the choreographs of the fighting, the sweating gave some light shorts to his skin, and for that reason suit needs to be off. Roto and lighting interaction needed to be added for those shots.

Can you explain to us how your create the animation on suit when the Sirens put it on Sam?
Several geometry animation were created within Houdini to present Eric and Joe as proposals of « surface » build up. During the same time, tracking was being done for both the cameras and the character. The character used witness cams so we can have different point of views  for the 3D track, adding on the top of the tracking deformation and animation of a soft body to make the tracked mesh as attached as posible in stereo

Final render was done in manta using Image base lighting of the set, and several passes were sent to comp to enhance bump/occlusion/speculars and highlights during the transformations.

How was the assets sharing between your studio and Digital Domain?
Geometry was sent through Maya files. Mainly was of a couple of sets and elements. DD use as their primary render VRay for the project, while Ollin use Renderman… So shaders were not possible to share.
Textures were sent as EXR files.
Versioning was tracked by Ollin and DD Production team

Did the stereo aspect caused you some troubles?
More than trouble, is a complete different pipeline for several proceses in the VFX production:
– Tracking is done completely different.
– Compositing needs to take care of Vertical disparity, Lens aberrations between eyes, Polarization differences and needs to mantain information of convergence and interocular distance so artists can check the depth of their shots accurately.
– Reviewing between facilities and even with the director was in different stereo projection systems. Ollin uses Shutterglasses with a Barco Projector, DD uses RealD Polarized projector, and Joe sometimes was reviewing in Skywalker sound with a Dolby system.

What was the biggest challenge on this project?
Definitely the Stereo issue was the biggest challenge, as we had to re-design our pipeline.

Was there a shot or a sequence that prevented you from sleeping?
Hahaha… Several! There were two reasons why the last year we had trouble sleeping, one was Trailers/teasers/comicon shots that needed to have a very strict delivery. This movie was extremely publiciced and needed a lot of quick turnovers for specific shots. Not all of them were complicated, but to be able to present with the quality needed on a very short time was a bit painful. The other big problems was with tracking of some shots that had a problem in one of the stereo lenses. Specifically 18mm lenses during the entire movie had a center miss alignment which lead to weeks of work to find a proper solution.

What is your pipeline and your software at Ollin Studio?
We have several proprietary tools for pipeine management, most of them written in python for attaching to Nuke and Maya. The pipeline is based in a SQL database, that tracks each shot version, metadata, information, artist that worked on the shot and dates.
PReviewing is done by one of our internal software called « Jefecheck ».
Houdini, Renderman, Maya and Mantra was used for CG.
PFTrack and 3D Equalizer was used for tracking.
We worked closely with the Foundry for Ocula developement and that tool really saved the day!

How long have you worked on this film?
About 14 months.

How many shots have you done and what was the size of your team?
260 shots, and the team was up to 45 at some point of the production.

What did you keep from this experience?
An amazing movie with a great solid pipeline for Stereo production. Working with such a visual director as Joe Kosinsky and a profesional team at DD lead by Eric Barba was a great experience also for understanding the problems and solutions for such a complicated movie with a big studio behind.

What is your next project?
We are working with Disney in a new big movie for this year… but we can’t talk about it yet 😉

What are the 4 movies that gave you the passion of cinema?
2001 : A SPACE ODISSEY
THE GODFATHER
CLOCKWORK ORANGE
STAR WARS.

A big thanks for your time.

// WANT TO KNOW MORE ?

– Ollin Studio: Official website of Ollin Studio.
– fxguide: TRON LEGACY article on fxguide.

© Vincent Frei – The Art of VFX – 2011