VIFX jumps aboard project to add convincing details.
When it became clear that Digital Domain could not handle the entire effects load for Titanic, some 150 shots were farmed out to VIFX (Speed, The Relic, the upcoming X-Files movie). The company's duties included putting full-scale people into two different miniature engine-room environments, and adding starry skies and visible breath trails to shots of actors going down with the ship.
For the engine-room sequence, VIFX composited live-action actors shot against green-screen into the real engine room of a working Liberty ship, which Vision Crew Unlimited had transformed into a 1/3-scale miniature of the Titanic's engine room (see accompanying on-line story: Ship Building). "The Liberty ship was a real ship whose engine type was similar to that of the Titanic," explains VIFX founder Richard Hollander. "But its engine room wasn't the right size, so we added people in the appropriate scale to make it look huge. The issue was getting the interactive lighting to look right. The second-unit director, Steve Quale, was a great help in doing that. The hard part was putting in steam and getting the composites to layer in perfectly."
The 1/3-scale "miniature" made these shots relatively easy to believe. The challenge for VIFX was to intercut its elements with shots of a separate 1/14.7-scale miniature supplied by DD and photographed on VIFX's motion-control stage. "The 1/14.7-scale miniature was tremendously small for the work we were doing, which involved a ton of lights," Hollander remembers. "We would rather have had a 1/6-scale model. The miniature wasn't quite done, so we also put a lot of detail on those portions that were going to be in close-up, because we planned to get within inches. We wanted to mimic the kind of lighting that would be in there for real a bunch of incandescent bulbs, rather a large ambient fluorescent fill so we used very little fluorescent lighting. The caged lights in the set were one layer of lighting, but the majority of light came from a fairly accurate representation of the overall style of the lighting, if not the position. We literally hid bulbs all over the place to create that look. There were hundreds of lights hidden behind pillars, behind major struts and peeking in from the sides. We did several motion-control passes on every shot: a hero, a smoke pass, an incandescent light pass, and a series of four or five different matte passes."
Hollander set up another stage where the VIFX crew could shoot extras on the ground floor and on platforms and catwalks against greenscreen. These people were later composited into the appropriate areas on the miniature set. "We shot a lot of elements. We composited anywhere from two to seven people in any given engine-room shot."
One of the more difficult shots involved a simple boom down from the upper portion of the engine room to the ground floor, moving past people on catwalks and toward the workers below. "We started off by doing a camera move on the miniature until Cameron liked it, but we ran into trouble when we expanded that motion-control camera move out to full scale," Hollander says. "I didn't have enough depth in my stage to complete the move, so I rescaled the shot. Since the floor was the controlling constraint, I scaled my move to it and decided to make everything smaller as we reached the bottom. We even hired shorter actors so that they were scaled properly to the move. There still wasn't enough space to shoot the full-scale and scaled-down moves in-camera simultaneously, though. In the end, I did the move on the 100-percent scale people from above, then just scaled that move down on our motion-control camera system and shot the lower part with the smaller actors. It wasn't forced-perspective; it was forced-scale or pseudo-scale. In a forced-perspective shot, you're fiddling with the lines of perspective, but here, our perspective was true. We just made everything a little smaller.
"Our CG supervisor for that section, Edwin Rivera, then composited three scales to make those shots look like one continuous move: the live-action scale for the upper section, the 1/14.7-miniature scale, and the .8 live-action scale for the bottom layer. I'm very proud of the complication, which made it very believable. The net effect is a humongous engine room with all of these people running around on catwalks and on the ground."
For Titanic's climax, VIFX added stars to the night skies behind the sinking ship. "Stars are miserable to do," Hollander observes. "Jim used a lot of handheld camerawork, so there was anywhere from one to three layers of affective motion in these shots, and we had to change the direction of the stars to match. We had to track the handheld movement and then layer in the effect of boat motion, so the stars would be moving and rotating [subtly and in sync]. After we dealt with the technical layer, Jim had an artistic vision, which we had to add on top of that. The stars are not vivid. The action in the movie is not about stars, it's about these two characters careening in the water. Those are the rules. The complexity of those shots the delicateness of the stars and the actual dynamics of how they move behind the characters is amazing."
Aiding in this effort was Silicon Grail's Chalice 2-D compo-siting software, the new version of which offers garbage matting and motion blur, as well as a procedural paradigm that speeds such extensive compositing work.
VIFX faced another challenge in trying to create icy breath trails that would emanate from actors' mouths, simulating the extreme cold that plagued the disaster's victims during Titanic's final hours. "We were shown these incredible close-ups of Kate Winslet and Leonard DiCaprio in the water, plus shots of other actors on the boat as it's sinking," Hollander recalls. "Cameron wanted to see light playing off their breath. Some people suggested using cigarette smoke, but I said 'No way.' I chose not to do it in CG either, because we didn't have enough time to develop the look.
"Instead, we built a cold room and shot real breath emanating from a real person surrounded by black velvet. It was a cheaper methodology. We had a light up above and we shot the breath from various positions; the breath became the only visible detail over the black velvet."
Hollander's team soon discovered there were other complex chores to tackle such as synching the breath to the actors' dialogue. "We actually tried having the 'breath people' say the dialogue, but that usually was not the best way to do it. Breath stutters; it's staccato, and it has different rhythms and volumes. In the end, we basically built a huge library of breath, and asked the animators to listen to the dialogue and add the breath in time with the actors' voices. That's what we did for a hundred shots, and we found out that it's not easy to do; it takes great skill and great trickery to make it look right. My CG supervisor for that stuff was Cheryl Budget, who managed a massive amount of work."
Unlike some others who have worked with Cameron, Hollander found that the director's exactitude made his own work easier: "The role for me on this show was not to be creative and come up with a million different ideas. Jim pretty much knows what he wants, and if you listen to him, you just converge on a solution. Once you get into that mode, it's fun. I wish all of my projects were like this."