Sunday, February 27, 2005

Evolution of Visual Effects

"The evolution of visual effects over my 18 years at Star Trek is really the evolution of visual effects. Because we worked in television we were able to use lower resolutions, so we pioneered a lot of things that became standard techniques in features. We were the very first visual effects show to have video tape as our final product rather than film. We started out doing 1 inch analogue and progressed to digital and now we're doing high definition digital technologies....My job has gone from director of photography and compositing supervisor, to sort of an orchestra conductor of a team of virtuoso digital artists."

Even today, Curry said, an average feature may have 200 to 500 visual effects shots, that take a year to produce. "We have 2 1/2 to 3 weeks [to do each show], and in the average television season we do 3500 visual effects shots."

Curry also explained the difference between visual and special effects.

"Visual effects basically are making a synthetic reality out of pieces that were photographed at different times and recombining them into something new, while special effects happen on the set, like making the doors open and close on the Enterprise." They often work together-for example, visual effects will enhance explosions created on the set by special effects. Visual effects also works with what the makeup and other departments do. "It's a very interactive process."

Working with Models

At first most visual effects were done with minatures. The Enterprise-D, Deep Space 9 and Voyager were 4-to-6 foot models. "Sometimes it took 60 to 80 hours a week trying to keep up with the miniature photography for the ships. Now most of it is done in the computer."

But Curry doesn't think that miniatures will completely disappear even in the digital age. He pointed out that the 2004 film "The Aviator" used airplane models. "There are certain things computers don't do very well, so I think that models will never completely go away...and with models, like with computer graphics and with actors, it's all about lighting. If you light it well it will look great. If you don't light it well, it will look artificial.

"Practical elements"

"In those [old]days, we had to use a lot of practical elements--- and I'd like to introduce you to the force field that was used on the Enterprise." Curry holds up a ball of silver tinsel.

"Sometimes we'd bounce laser beams off beer cans onto white cardboard, and depending on how we bent the beer can it would influence how the image would appear. We used these for force fields and tractor beams. It was fun--- a form of medieval alchemy."

The key to creating visual effects: "Teamwork, and the ability to perceive things not for what they are, but for what they might be."

Motion Control

"Doug Trumbull [special photographic effects pioneer on 2001,Close Encounters of the Third Kind and Star Trek: The Motion Picture among others) was visiting an airplane plant in the LA area and he saw these huge milling machines doing the same motions over and over again. [Before then] spaceship models were filmed on wires against blue screen, and with 'overcranking' (moving the ships at faster than 24 frames per second, the speed of the film).... you couldn't get any lights inside for windows or [vapor coming out]... When Doug saw the milling machines he had the inspiration that if you mounted a model in one place, and you had roll, pitch and yaw, he could build lights into it and photograph it slowly, one [frame] at a time, giving perfect exposure for each element of the shot. So Doug's great inspiration was the contribution that made visual effects possible not only for Star Trek but Blade Runner, Star Wars, all those early films---the value of his influence cannot be overstated."

Each time a motion control pass is made, new elements are added. "For the [TNG] Enterprise and Voyager fly-bys we had to do the same thing seven times. [It looks great when it's done, but] watching a motion control shot has all the visceral thrills of watching cattle graze."

Sometimes motion control is shot against an orange screen "for matte passes or silhouette passes, lighting with ultraviolet light. Orange screen gave us a very even field of light---it made it easier to pull out an accurate silhouette of a ship."

Computer Graphics

Then came computer graphic design. Curry demonstrated how computer animation shots evolve, from "a wire frame [of the object] to adjust motion, then a smooth shape that gives us a sense of the volume, then the final render[ing]. The wire frame and smooth shape are used because the final render can take a long time. For one series of shots, it was 17 hours per frame."

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