The Homing Beacon, the official Star Wars newsletter, issue 81 has as its main story the role of the Model Shop at ILM, with comments from ILM veterans Lorne Peterson and Steve Gawley.
Titled Backbone of Reality, here it is:
Since the beginning of the Star Wars saga, the Industrial Light & Magic model shop has been crafting vehicles and locales from a distant galaxy, continuing a decades-long tradition of miniature work standing in for things that would be impossible or impractical to create in real size.
Nowadays, the computer has taken over many visual effects disciplines, but there is still a need for the model shop, which has become increasingly high-tech alongside the digital innovations. Its task is similar, but with a new twist: the model shop is crafting practical miniature work for things that would be impossible or impractical to create in CG.
"Many times practical miniature effects have proven to be a very efficient solution to some challenging shots that film directors envision," says Model Supervisor Steve Gawley. "We often use computer aided machines to fabricate true 3-dimensional parts that are derived from computer files we generate. We also use digital files from the CG group as well as providing 3-D maquettes from which digital animation elements are built."
As a facility, ILM is involved in a dozen different projects at the same time, and Episode II had over 2,000 shots done over a two-year period, which is really aggressive," explains Vice President of Creative Operations Jeff Mann. "As a company, you can only do so much in the digital pipeline. We have to make decisions about how to do all of that work at the same time, and you just can't do it all in the digital world. The decision comes down to what would look the best and be the most cost effective. Miniatures and models play a key part in things like pyro effects, where you're having to blow things up and control that kind of shot, or when you need realism in a 3-D landscape."
"Sometimes, the model shop picks up shots near the end of that pipeline, if CG gets totally booked up," explains Lorne Peterson, Model Supervisor. "Many times, we'll be relatively free right near the end of production, so we can do a Geonosian ground plain for the last battle. Sometimes it's money and time. Sometimes it'll be more expensive to do things in CG than it does to do the model, so the model shop will get those shots."
Once the decision has been made to create a miniature, the next step is to figure out how much of that miniature to build, and at what scale. Usually, digital animation and practical miniature effects are combined, as the models give a backbone of reality to shots, like the inner dome of the Kaminoan training facility, or the far wall of the Geonosian droid factory.
"After you get the design drawings, you have to go back to the storyboards or animatics, and decide what kind of model you need," says Gawley. "Many times, you don't build the whole thing. It's through the vision of the director and what he wants to happen in a scene that we then give an estimate of what to build. If everybody agrees on what's needed in the miniature world, we go from there."
"There are times when we go outside to the parking lot and lay out with tape how big the different models will be," says Peterson. "We ask, 'do we want to pay for one that size or do we want to pay for one this size? Will that do for your shot or will this do for your shot?'
Large miniature sets are still photographed outside, in ILM's parking lot, to take advantage of the California sun for lighting. This practice dates back to the original Star Wars, when Death Star surface segments were shout outside in a relatively low-tech fashion: a VistaVision camera mounted on the back of Steve Gawley's pick-up truck drove past the miniature in the lot. "I think Steve told me that he was paid an extra $50 to have his truck next to the explosions," laughs Peterson.