The secrets behind Star Wars' special effects

Lighting with blue screen

Lighting with a blue screen background in what was supposed to be deep space could still be a challenge. Using the Death Star as our example, when one side is lit, as if by sunlight, and the other side is dark, the dark side will reflect blue light from the screen: the dreaded blue spill.

"In order to wash out the blue spill we had to have about a 3:1 contrast range on the model; in other words, if the key was 125 foot candles you had to have about 25 to 30 foot candles of fill in order to wash out the blue spill. So we had fill light in space, but Star Wars is kind of a fantasy, and so we got away with it."

Lighting the Death Star against a blue screen background was a challenge

John Dykstra, Grant, Bill Shourt and Dick Alexander used to take their dirt bikes out to Randsburg, an old ghost town in the Mohave desert. Randsburg was once a silver mining town, and used a method called sluice mining, the process of shooting high-pressure water at decomposed granite to extract the embedded silver.

The silver would settle to the bottom as the sluice would run down a trough and eventually down the hillside, leaving behind a layer of fine sand. "As time went on this fine sluice run-off eroded and became a miniaturised canyon. We used this as a backdrop to shoot the sand crawler, working with small miniatures.

The sand crawler model was only about 16 inches high, 20 inches long and 10 inches wide. I think the approach of using small scale miniatures really helped us out. They are much quicker to build than bigger miniatures, and much easier to light and shoot. And our time was getting short."

Space-age budgets

"I did all the shots on the Millennium Falcon, or what Grant called the Pork Burger." At almost five feet long, the original Millennium Falcon was big and heavy. "George came in and said, ‘you know, that looks too much like Space 1999. Let's come up with a better shape.'

"I think Joe Johnston came up with the round concept and the guys in the model shop built it. It was still very heavy, weighed at least 100 pounds. It needed to have a mounting post, about a 2 foot, 5 inch pipe, whereas the X-wings, Y-wings and Tie Fighters all had ¾ inch mounting rods.

"The thing about VFX is you never know what is waiting around the corner to trip you up"

"Those were much easier to deal with, and you could set up and get ready to shoot in much, much less time. It took a lot more time to shoot the Millennium Falcon."

"The thing about VFX is you never know what is waiting around the corner to trip you up, so you constantly have to be on guard with your inventive mind in order to figure out how to paint yourself out of the corner. It's become a lot easier now, but notice how much more expensive it's become.

"Visual effects budgets are now reaching tens of millions on the big tent pole movies, and in Cameron's world they are in the hundreds of millions." And it all started with just $2.5 million and some brilliant ex-hippies.

Words: Renee Dunlop

This article originally appeared in 3D World issue 189.

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