'Be Kind, Rewind': Getting in VFX Synch with Gondry

Director Michel Gondry is known for making truly original movies. After Eternal Sunshine of the Spotless Mind (2004) and The Science of Sleep (2006), he is back with a new and completely intriguing storyline. A man (Jack Black) whose brain has become magnetized, accidentally erases every tape in his friends video store. In order to save the day and to satisfy the few loyal customers, the two men set out to remake all those movies themselves

Once again, visual effects were key to bringing this story to the screen. In The Science of Sleep, the vfx were very stylized and, as such, noticeable; on Be Kind Rewind (which opened Feb. 22 through New Line), they had to be essentially invisible. There are only a couple of sequences in which you do know that there are vfx, and thats because they couldnt have been filmed any other way, notes Visual Effects Supervisor Fabrice Lagayette, who oversaw the project at BUF Compagnie, Paris, with VFX Producer Cynthia Mourou. When our hero Jerry gets electrocuted, it obviously is CG animation. Jack Black was filmed suspended by cables in a set that was lit by interactive lighting. We then animated 3D lightning bolts synchronized with the practical lights. We also re-lit Jacks body every time the character was hit. That probably was the most visible part of our contribution to the movie. We did about 100 shots over a period of eight months. As always, Bufs artists only used proprietary software on this project, except for rendering, which was tackled in mental ray.

Rules of Attraction

Other noticeable visual effects involved highlighting the fact that Jerrys body was highly magnetized. We had a sequence in which Jerry urinates and we see how the liquid affects its environment. We used to call it the magnetic pee sequence, Lagayette laughs. It took us quite a bit of R&D to establish a look. Should it look entirely normal? Another color? Chrome-like? Should there be a halo of any kind? We did many tests that we submitted to Michel, who opted for a fairly subtle look. He didnt want it to be cartoony. It had to be funny, but not so outrageous that audiences wouldnt buy it. That was true of all the movies vfx. We had to establish a fine balance between realism and comedy.

Buf started with a plate featuring a pool of liquid on the ground. The first step was to build a 3D environment map to be used as a reflection on the surface, which was also recreated as a 3D geometry. Using this reflection map, the team was able to emphasize the otherworldly nature of the liquid. Then, several objects -- bolts, screws, etc. -- were modeled in 3D and animated in the liquid to look like they were being pulled with it. The team also rotoscoped a nearby car, and re-projected the image on a corresponding 3D geometry to animate extravagant vibrations.

We also had other sequences in which we see how Jerrys body reacts to the environment, adds Lagayette. In one of them, Jerry walks along a fence in a street and his body is suddenly and brutally attracted to the metal mesh. It was one of those sequences where we really went pretty far in the animation in order to create a comical effect. The plate was shot with Jack Black simulating the action, but Michel wanted something that would be much more spectacular and surreal. So, we rotoscoped Jack Black and painted part of the fence out. Once we had a clean plate, we recreated the fence in 3D and animated it to start vibrating much earlier and far stronger that it had in the original footage. Then, we took Jack and greatly accelerated his movement towards the fence. We had to do many tests to find the right timing. Once Michel approved the 2D animation, we composited Jack back in and animated the fence to simulate the impact.

Crafting the Opening Shot

Another sequence required similar work on the environment, albeit on a much larger scale. The movie opens with the camera flying high above a freeway. After a moment, it tilts up to reveal the Manhattan skyline and an overpass in the foreground. The camera then goes down under the overpass and finally catches up with Jerry. The shot was simply impossible to capture in one take. Michel Gondry shot it in three separate passes: a helicopter plate over the freeway, a crane shot starting at the helicopters final position in front of the overpass and ending at ground level, and a dolly shot.

Buf was called in to create transitions between the three plates to form one continuous shot. It was definitely our biggest shot and, guess what, it was the last one that we started working on, Lagayette smiles. Editing gave us a locked cut of the sequence two months before deadline only, and it was huge! To start with, for safety reasons, the helicopter plate had been shot over a closed freeway. There was no traffic whatsoever in the original plate. We had to create it all in CG. Then, the three plates didnt really match. The timing was quite off, the camera angles were different, and the light directions were not the same, which meant that we didnt have matching frames to create a 2D transition. It had to be 3D transitions. In fact, it got so complicated trying to link those three plates that we ended up replacing the whole middle section with 3D animation. Finally, we had to add Manhattan in the background as the plates had been captured in a nondescript location. So, it was quite an undertaking -- especially when you considered that it was a 2,300-frame shot.

The team started by tracking the various plates. Using an off-the-shelf database of car models and in-house archives, they set out to build a realistic traffic. Artists assigned each vehicle to a predetermined path that followed a specific lane on the live-action freeway. The speed and distance between each vehicle was also pre-determined. The fact that we had to recreate the traffic in CG turned out to our advantage in the end, notes Lagayette. It allowed us to greatly accelerate the timing of the helicopter plate to get a more dynamic shot. The cars speed was simply adapted to the helicopters new speed. Since we didnt capture any HDRI information on set, we selected a plate image that contained the most visual information on the environment, sky included. Then, we used it to create an environment map that allowed us to light our CG elements in a realistic manner.

Buf also added all the electricity pylons along the freeway. None existed at the actual location. Buf based the CG construction on a partial set that represented the bottom of one of the structures on location. Once we were happy with the helicopter plates, we set out to link it to the live-action dolly plate. In order to do so, we modeled the whole overpass location in 3D, and re-projected the second plate -- that had been captured with a camera crane -- on that geometry. When that didnt suffice, we went back to the end part of the helicopter plate and used that as another camera projection to start our 3D transition. Specific elements were modeled and textured to fill in when the original plates didnt have the visual information that we needed for the new camera movement. Finally, Manhattan plates were used to create a background matte painting that was tracked in the virtual shot.

Seamless Transitions

Lagayette and his team faced a similar challenge with a lengthy shot in which we see our heroes comically re-incarnating some of the most famous characters in movie history. The shot had been captured in many different takes and Gondry wanted to combine several successive performances in one single shot. It implied creating seamless transitions between parts of different takes, all shot without motion control and with huge variations in comical timing. We managed to create most of these transitions using 2D morphings, but there was one case for which we didnt have a piece of set that linked the two actions. We had to recreate the environment in CG in order to connect the two plate elements.

Parallel to these creative effects, Buf also worked on a great number of miscellaneous fixes. That included re-timing shots for better comedic effect. Using split-screen techniques, the team would isolate one part of the frame to extend or to compress the duration of the action in order for it to better match what was happening in the other part of the frame. Typically, that would be one character ducking to hide from another character. By adjusting the timing digitally, we could alter the succession of events and create a more interesting scene. We also had a scene where Danny Glover writes a note on a window that is covered with condensation. For a variety of reasons, the plate was shot with the whole text already in place. Then, we created an animated matte to reveal the letters as Danny Glovers finger was tracing them. It was one of dozens of invisible fixes that we did on this project.

Invisible VFX Supervisor

The most unique aspect of the movies visual effects is actually not the way they were realized; it is the very approach that was used to capture the plates. Having worked with Gondry many times in the past, Buf Compagnie has reached a point where it knows exactly how the director works. As a result, Buf decided that the visual effects supervisor shouldnt interfere with principal photography at all, in any way. In fact, the visual effects supervisor never even put a foot on set! Its true, I didnt go on location with the crew, Lagayette confirms. I discovered the shots as I was getting the plates. The advantage of that approach is that it provided the director with unlimited freedom. Michel could shoot exactly the way he wanted, and he never felt any constraint at any time. That was especially important to him as he always improvises a lot.

Alain Bielik is the founder and editor of renowned effects magazine S.F.X, published in France since 1991. He also contributes to various French publications, both print and online, and occasionally to Cinefex. In 2004, he organized a major special effects exhibition at the Musée International de la Miniature in Lyon, France.