Collected Essays (23 page)

In making any film, the producers try to shoot as much of it as possible with actors, sets, props, backdrops, and people in costumes. It’s up to companies like ILM to enhance the master film by adding the missing pieces: the chrome robots, the spacewar dogfights, the cosmic backgrounds, the melting flesh.

The traditional method of doing this is to build scale models and paint mattes of the missing pieces—a matte being a large, detailed painting, often on glass with part of it left transparent so that a moving film image can be set into the gap. Films of the models and mattes are made, and these model films are then layered onto the master film by a process called optical compositing.

How does optical compositing work? If you’re doing something like, say, adding spaceships to a sky background, you might film your model ships and project these model films onto a big screen that is showing a film of the actors beneath the sky. Then you film the combined images directly from the big screen.

If there are only one or two elements to add to a scene, optical compositing is quite cost-effective. But scenes like a space-battle or a dinosaur stampede can involve dozens of different models, each of which needs to have its image added as a separate step.

To get around the problems of optical compositing, ILM and Kodak jointly developed a machine which can turn a frame of film into about twenty megabytes of digital information. In a fine example of industrial altruism (or buck-passing), Kodak calls it the “ILM scanner,” and ILM calls it the “Kodak scanner.” It’s a bulky device that looks like a workbench with lenses on top and computers underneath.

The point of scanning film images into digital form is that it then becomes much easier to cut and paste the images together. Each part of the process is perfectly reversible, and you can undo old things without harming newer additions. Optical compositing gives way to digital compositing.

Of course once you have the ability to turn your movie film into digital images, the entire range of digital processes become accessible to you. It’s easy to erase the guy-wires that are used to make a truck fall over in the right direction, for instance. And, most radically, you can add in computer-generated images that are not of any physical model at all. Let one byte of a computer into your tent, and it drags all of cyberspace in there with you.

Computer animation was used to a limited extent for the water snake alien of The Abyss and for the chrome-skinned robot of Terminator 2. When it came time to create the dinosaurs for Jurassic Park, the computer graphics faction at ILM decided it was time to go digital in a big way.

“We began planning for Jurassic in December, 1991,” says Mark Dippé, an ILM Visual Effects Supervisor who is a strong advocate of computer animation. “There was a question of should we use computer animation or should we use latex puppets over metal armatures, along with men in rubber suits and some big hydraulically driven arms. The problem is, you can only shoot a hydraulically driven device from one angle. And a man in a suit moves wrong. And a puppet can’t readily roll on its back if the armature is on its left hip. There’s limitations from the physical things. And when you want a herd of animals—are you going to build five hundred rubber models?”

Dippé and his group modeled their first virtual dinosaurs by measuring some dinosaur sculptures. The resulting numbers were used to create computer meshes: assemblages of mathematical triangles in three-dimensional virtual space. Next came the problem of writing programs to move the meshes around in a realistic way. “We had to communicate their massiveness,” says Dippé. “What do they notice, what are they afraid of, are they wary? We shot photos of each other acting out the dinosaur roles. We played with little puppets. The others still weren’t sure. But I knew this was the opportunity. And in spring of 1992 we had the deal. The computer animation team has about twelve people, and they’re shifting us into every arena.”

Adding computer animations to a movie involves four steps: modeling, animating, rendering, and compositing. A model is a three-dimensional static model of an object—like a wireframe dinosaur. In animation, you set some keyframe positions you want the thing to be in, and have the computer smoothly fill in the positions between. Rendering converts the computer’s three-dimensional model of the camera, the lights, the objects and their surface textures into a two-dimensional image. Compositing is combining your rendered image with the film of the background, with the matte paintings, and with the film of the actors. A typical shot involves doing this for a couple of hundred frames.

The old “animatronix” approach to positioning a model was to have the model be a foam and latex creature built over a hinged metal armature with lots of little motors. A wire or a radio control would connect the motors to a puppeteer. But, points out ILM programmer Eric Enderton, “As soon as you have a data link like the radio control, you can replace either end by a computer.” Using this insight, the computer animation group built a skeletal data-dino which they could move around to change the position of virtual dinosaur skeletons inside the computer. The data-dino acts like a mouse, or like a data-glove. The skeleton on the screen emulates whatever pose the data-dino is in.

Once the virtual dinosaur skeletons could be positioned at will, there came the question of the dinosaurs’ muscles. Mark Dippé says, “We attached models of muscles to the dinosaur bones, and then we assigned one guy to be the muscle expert for each dinosaur. The muscle expert had to program a complex procedural system of relationships between the muscles and the angles of the joints. The shoulder, for instance, affects the a lot of muscles. And if some muscle doesn’t swell dramatically enough, we use a secondary set of muscle controls called bulgers.”

At the rendering stage, the material of the dinosaurs’ skins was taken into account. What kind of colors and textures go into the tiny triangles of the moving wireframe computer meshes? “Part of the game is image complexity,” says Enderton. “And on a computer you have to work for everything. One trick is to bring real world information into the computer. You can scan in actual skin textures. But we had to do more. The dinosaurs’ skin was a big deal.”

“We finally ended up building a three-dimensional paint system called Viewpaint,” adds Mark Dippé. “You get a three-dimensional computer model, and spray some paint onto it. Then you turn the model and the paint turns with it, and then you paint some more.” In addition to colors, the “paints” which Viewpaint can apply include such subtle things as shininess, dirtiness, bumpiness, and the coarseness of a dinosaur’s reptilian scales. As a final touch, the skin textures were subtly roughened with computer-generated chaos to give them the indefinable level of detail that characterizes images of the real world.

This seems like an unbelievable amount of work for one movie but, as Dippé happily points out, “All the dinosaur technology can be used again for The Flintstones. The dinosaurs are vicious in Jurassic Park, they have to kill to exist. But in The Flintstones they’re like people, they’re pets, they complain, the escalator is dinosaur in a hamster wheel, they’re more anthropmorphized. But the techniques are the same. And it doesn’t just have to be dinosaurs. We can do all forms of animals now. And superheros are okay, too.”

What next? Enderton says, “The holy grail is to do a believable human in clothes—a human with cloth and hair. This is hard because you know exactly how a human moves, reflects light, and behaves. You’re never seen a live dinosaur, which was an advantage for Jurassic.”

The success of digital compositing and of the computer animations for Jurassic Park has set off a small upheaval within ILM. The tinkerers in the creature shop and the model shop feel threatened. “I liked working on a stage with lights, making something to look real,” recalls Jeff Mann, former head of the model shop, and now Director of Production Operations, which creates digital mattes. “There’s a camaraderie in the production aspect; you have a common goal to make it real. We worked for ten years to make the process flow smoothly, and it seems weird to suddenly do it all on one work station. The change to work stations is happening so fast—it’s like the Richter scale. It’s stressful for a fair number of the model builders. ILM is trying to retrain the optical compositors as digital compositors, and to teach some the model builders to use the tools of the computer to build computer models. Some will be able to adapt, some will get to keep building models, and some will go do something else.”

But models are not going to fade out overnight. Even in Jurassic Park, the old-style rubber models were used for many scenes—such as the one where the T. Rex attacks the car. For each shot, it’s a question of which technique will get the job done for the least money in the fastest time. Despite ILM’s recent alliance with the Silicon Graphics computer company to form a Joint Environment for Digital Imaging (JEDI!), convincingly realistic computer animations are still very expensive. As Dippé puts it, “A movie like T2 or Jurassic is like building the pyramids.”

The model builders refer to their creations as “gags.” They’re like elaborate practical jokes, in a way, things that can fool your naked eye. They’re fun to be around.

An example. As I was touring the creature shop with Mark Dippé and the ILM publicist Miles Perkins, Mark suddenly said, “Hey, Rudy, look at this!”

I walked over and Mark pulled back a sheet that had covered a tortured rubber man on an operating table. Leaning over him was a rubber alien wielding something that looked like dental apparatus. Suddenly the tortured man began to move and twitch. I screamed. The gag was a hidden cable leading to a control in Miles’s hands. This was fun. I thought about Jeff Mann’s wondering if working on a work station could ever be as much fun.

While I was in the creature shop, Miles mentioned to me that the main stash of old models and creatures is in the ILM archives, located at Skywalker Ranch, a half hour deeper into Marin County. I had an instant mental image of the great hall where the crated-up Ark of the Covenant gets stored at the end of Raiders of the Lost Ark. I knew I had to go.

Several days later, I drive with ILM head publicist Lisa van Cleef up a misty winding valley towards the California coast. The Skywalker Ranch includes George Lucas’s offices, a sound studio, and guest quarters for visiting ILM customers—such as Steven Spielberg. Everything is California perfect, like the best weekend retreat you can imagine. The sound studio has a small vineyard in its front yard, a gift to George from Francis Ford Coppola. There’s even a small fire department and a small working ranch with a few dozen cows—- both these features having been mandated by Marin County before they’d approve the construction of Skywalker Ranch. Since the cows aren’t really there for ranching, they’re prop cows, which seems appropriate.

There are three or four men busy working on models in the archive building, and one of them, Don Bies, acts as my guide. “You’ve come at a really good time,” he tells me. “We’re just restoring the Star Wars models to send them on tour to some museums in Japan.” Here in the archives the model builders are happy, and the work stations are far away.

The first gag that catches my eye is a baggy humanoid shape, orange with green spots, rubbery, with a hula skirt bedizened with electronic parts, and with a face sporting a three foot snout with red-lipsticked lips on the end. “That’s Sy Snootles, the singer from the band that plays in Jabba the Hut’s castle in The Return of the Jedi,” Don tells me. I pick up a handgrip connected to a cable that leads into the figure’s back. When I squeeze the grip, Sy’s lips purse.

Right next to Sy Snootles is Darth Vader’s costume. The cryptic alien writing on the little control panels on his chest is Hebrew. “Not many people realize that Darth Vader is Jewish,” smiles Don. “Notice also that he’s clean. Darth Vader and the robot C3PO are the only shiny things in the Star Wars universe. Everything else there is grungy.”

We turn next to a yard-long spaceship model. “We wanted to make this the shape of an outboard motor that’s been rocked up out of the water,” says Don. “For the details we used a technique we call kit-bashing. We include a lot of pieces from standard model kits. See that there, it’s the conning tower of a submarine, and here’s the hull of a destroyer ship, and this down here is the front of a jet plane, and up here is part of a helicopter.” This kit-bashed spaceship is a reality collage. The computer graphics animators scan textures from reality, but the model makers just break up and reassemble reality.

“Where’s R2D2?” I ask. He’s always been my favorite.

Don points, and I turn to see a whole herd of R2D2’s in a far corner. There are eleven of him. Why so many? Because when Star Wars was filmed, the science of radio-controlled machines was quite primitive, and it was easier to build a different R2D2 to do each of the different things he was supposed to be able to do: turn his head, roll, fall to pieces, and so on. Each R2D2 has a big “holographic projector lens” near his top. The lenses look familiar because—they’re those movable nozzle lights that airplanes used to have over the passenger seats. “And those slots along his side are from coin-operated vending machines,” Don adds. It’s kit-bashing in a higher, more industrial way.

Now we come to the gilded Ark of the Covenant itself, resting beside a busted-open wood crate. Stenciled on the crate is “
Eigentum Des Deutsches Reich
,” with a swastika. I really am in the Raiders of the Lost Ark warehouse, and now, yes, Don opens a cabinet and he pulls out the matte painting of the Raiders warehouse scene, a giant sheet of glass with piles and piles of boxes fading into the painterly distances, and with an irregular trapezoid of clear glass where the image of the moving warehouseman was projected for optical compositing.

The ceiling struts in the matte painting seem to match the struts in the archive room, and when I go back outside and the foggy beauty of this hidden valley spreads out before me, it’s hard for me not to believe, for a moment, that I am looking at an even huger matte painting.