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"Normally, I'm not a fan of bluescreen work," admits Stefen Fangmeier, special effects supervisor for The Perfect Storm, who has also overseen on-screen magic for Jurassic Park, Twister, Speed 2: Cruise Control, Saving Private Ryan, Small Soldiers and Galaxy Quest. "Shooting live-action foregrounds and putting CG elements behind them without using bluescreen makes the work labor intensive, but you gain the look of real lighting and atmosphere, the sense of being there. Although the technique is constantly improving - look at Mighty Joe Young, as a recent example - I can still tell every time that I am looking at bluescreen work. "On The Perfect Storm, however, we didn't really have a choice. We had to shoot against some form of backing on stage, with the boat on the gimbal and all the action going on in the very large tank. The goal was to create the complete environment around that set, to give the impression of the highly atmospheric situation one finds in a severe storm at sea. We had to find a way to make the bluescreen look good, to put in layers of elements to ensure that the photography never looked pasted-on or our CG waves behind the boat appeared as a rear-projected image would." Consulting with director Wolfgang Petersen and cinematographer John Seale, ASC, Fangmeier had to define exactly how much storm work could be done on the set and what would have to be generated at the Industrial Light and Magic facility. "They would be working with mist, fans and water canons to generate the moisture and mist in the air," the effects artist explains. "Very quickly, the bluescreen would get contaminated. How much could we 'hold back' on set so that that didn't happen? Would we have the ability to put in that force later in post and make it look real?" Fortunately, ILM's in-house computer graphics programs have become so sophisticated that such substances as "fine mist" can be carefully integrated at several distances from camera. Thus, the team could define the tools' boundaries. "What happened was that we began considering the limitations on stage. Just how wide of a shot could we get within Stage 16 on the Warner lot? How much movement could the gimbal give us? Early on, we learned that we could not go very wide with the real action. Hence, when the film needed to be opened up to give the audience the sense of being out at sea, it fell to ILM to create the storm's larger segments. We were able to enhance the audience's perspective on the situation by adding distant waves in the background and foreground." What produced such a successful collaboration between Petersen's production team and ILM was the in-sequence editing process of the director's storyboards on an AVID system. This rough timing - enhanced by the next step of 3-D CGI animatics - empowered them to literally frame a shot and produce what would be seen by the camera in any given situation, using a computer model of the Andrea Gail on the ocean. "It wasn't the greatest visual quality, however, it did allow us to decide what framing we would use and even what lens," says Fangmeier. "Storyboards lack camera moves and an absolutely realistic perspective. Three-D, CGI animatics allowed us to clarify how we would do a certain shot. With all the physical limitations on set, it became obvious when seeing a move of the boat and camera in three dimensions whether this could be done on stage or would have to be an all-CG shot. "John [Seale] had to deal with cranes that would be hit by really high winds, for example. Once it was decided to shoot it on stage, the animatics merely became a guideline, since John and Wolfgang wanted to 'find' the right angle, as they would on any other non-effects shot. Remember, this was a very difficult set to photograph and get the dynamic moves that we could so easily do in CGI, simply because of the physicality of the shots." The animatics aided every department's understanding of what elements were needed for each shot. By plugging in a tape and viewing the sequence from a somewhat defined perspective, everyone involved could ascertain the thought process behind the shot in question. The shots might have been low-resolution but communication was the central factor. One could clearly observe how the "camera" would "come around the bow," for example, leaving a means for how to best define ways of "buying" the movement. "Sometimes, a technique like this can be termed 'costly,'" Fangmeier admits. "However, results outweigh the cost when you are tackling a job like this." But animatic visuals only comprised part of the task at hand. Fangmeier also concentrated on lightening the load for the on-set crew. "There were times, when I was on the set, when first-unit was trying hard to get things to be 'perfect,'" he says. "Because of the sophistication in CGI work, I was able to say 'Let's move on now,' and they knew we could fine-tune things in post. Although that is always a temptation, I am still careful that 'fixing-it-in-post' is necessary, and so were Wolfgang and John. Digital technology should not be that readily employed to fix things which could not be anticipated during the planning of a shoot. There is nothing that works as well as getting it right for the camera, and this crew certainly worked very hard to do just that," he adds adamantly. In Fangmeier's mind, the spectacular shot seen in The Perfect Storm trailer - that of the Andrea Gail careening up a grandiose wave - best illustrates the multiple complexities behind ILM's computer-generated imagery. "It shows all the different issues that we were dealing with," he expounds. "We could never have gotten the camera that far away from the boat on set, or changed the angle and made it real, for one. The most movement we could get from the gimbal was about 15 degrees, but this was one of the many shots that required a lot more. Then there is capturing the water - it's a powerful force - and the visual believability factor." The CGI crew's greatest hurdle came when creating the Atlantic Ocean's seething gales. Fangmeier and associates began the process of defining the water "look" by determining the parameters of actual wave motion. "We first had to understand that we were dealing with a reality," he explicates. "This is not a made-up world like Small Soldiers or Galaxy Quest. Everyone knows [or thinks they know] what real water looks like, just as they know what a dinosaur would look like, even though the creature is extinct, which we had to keep in mind when doing Jurassic Park. "First, we had to define what the water surface would look like, and under various lighting situations [pre-dawn, early morning and diffused light]. Up until now, we've always tried to deal with CGI work in strong light sources and deeper shadows. That was not possible for The Perfect Storm. We needed diffused light and overcast conditions, which was extremely difficult to model. Think of it like having a huge Fisher light overhead. That's what the sky became for us. "There is a certain marbling that happens when foam goes up a real wave. There is a definite sense of movement going up that we had to capture. Then there is also the boat's interaction with the waves. At the bow, there is foam generated as it cuts through the water - this might be blown by the wind. Then it hits the water again and gets pushed away from the boat by the bow and stern wake. We had to tie all this together - every little part had to have its own correct dynamics. "The water surface itself wasn't the most difficult - the combination of the elements became the challenge. There are capillary waves, smaller waves and foam that forms, changing the surface even more. Then, of course, there is the wind that tears across the waves and whips that foam off, making it interact with the air. "Multiply these challenges by distances as well. A ripple structure looks different when it is 100 feet away than when it is 10 feet away - both had to work visually. Now add the boat cutting through the water and, well, you get the idea. It's the 'Domino Theory' - the light, the texture, everything was very inter-connected. As soon as one element was off - too bright, too fast or not looking wind blown enough - everything else would be off. We were constantly striving for that balance. One of the advantages that Fangmeier and team found with the digital medium was its ability to easily modify gradations in color. As each shot became specified, they could observe its hues, altering them subtlety until reaching the proper tonal balance. "Although our tools aren't as responsive as moving a light on set, we do have the benefit of working with an interactive creative process." Fangmeier and the ILM team had a battle plan, so to speak, defining their wave making in stages. "It went from 'Woody Allen' to 'Jack Nicholson,'" he says, laughing at his own analogy. "We began creating a character that whimpered and ended up with a full-blown rage." But as far as lighting goes, the whimper might have been a little easier to produce than the rage. "Much of this storm takes place at night," indicates Fangmeier. "Initially, we thought that was great because we could work in the dark a lot easier. But we then realized that it was actually more difficult. We had to factor in the lights from the boat, the work lights, how the boat was shot on stage, and what 'local illumination' onto the surrounding waves would show. "In such a severe storm there wouldn't be any moonlight. So we couldn't make a 'Hollywood night' - a night that wasn't really night. We found different ways to show our star, the ocean - from lightning flashes established in the stage photography giving glances at the monster to lightning hits in the distance - so we could open up the shot to show that this boat is battling through a vast, raging sea." According to Fangmeier, these accents tended to vary from moment to moment. What might have worked for one shot didn't make the grade for another shot. Diffused situations, along with specular and reflection kicks on the water, all present quite different aspects of modeling the surface with light. ILM's unit became permanently stuck on the "learning curve"- both creatively and technically. "We expected that once we had figured out the technology, we could speed up the process and complete shots more quickly as we progressed through the schedule. Well, this never happened. Without a doubt, water is one of the most fickle things to light in CG. "Then there was always the question of how much mist to put into the air and what we could use to illuminate it. When a storm gets going, the vaporized water in the air becomes extremely dense. It's like filling a whole stage with fog and turning a dozen fans on to make it swirl around. It can't be so dense that it obscures the action, but not so clear that you can see through it and hence not get to 'feel' the storm. That was still another fine line to be navigated for every single shot." Though Fangmeier admits the importance of the authenticity issue, this factor was not as crucial as it might seem. All their digital deception had to not only function with precision, but also work within the film's framework. "It was more about keeping the viewer in the story," he notes. "We began with reality. We studied the science of waves, for example. However, there are points in the story where our waves just didn't seem big enough. They might be scientifically correct, but they didn't have enough 'movie impact.' So they had to be pumped up, so to speak. But it's important to know the scientific theories behind what is being re-created, specifically to be aware of when you are slightly over-stepping that bound. "Take the example of the waves you might see when looking down onto the ocean from a helicopter. Forty-foot waves might seem like nothing from there, but they had to be something on the screen. We had to up the ante, no doubt! That's why the final sequence is virtually all CGI. It had to be wider and larger, and it was simply impossible to capture with the camera on the stage or even in the real water. We had long conversations with John, about how he would have lit these shots, and then transported his ideas into digital terms." "We always had to keep in mind that people have seen water," concludes Fangmeier. "They have been to the shoreline. They have seen waves crashing, they have seen mist and they have seen foam. They might not have seen such a huge storm, but they can tell [the difference between real waves and fake ones]. Giving the audience the reality they would believe - one that would look real, threatening and deadly at the same time - was what made it so hard." |