In addition to the acting skills required to play any role, acting on "Sanctuary" requires learning and becoming comfortable with the production process.

"It's not that much different than actually shooting on a real set, once you get over the Chroma key-green headache, which lasts about three days.," said Tapping, who's also one of the show's executive producers. "Our director of photography, David Gettis, is an artist, and he paints with light. It's the best way I can describe it."

She said the challenge is "just getting your head around the idea of being inside a totally virtual set. We talk to our director and our vis-effects team, and we often have renderings that we can look at before we actually step onto the stage, so you get an idea of the scope."

Although mistakes can happen when you're moving around an empty soundstage without being able to see anything that's going to be there when the set is digitally constructed.

"Every now and then we'll have a chase and I'll run through a wall or something by accident," Dunne said. "And Martin will have to call cut and give me the parameters again."

If you're making a movie with CGI sets, all you have to do in a situation like that is put the wall in a different place when you create the digital set.

"When you have standing sets that are virtual that you have to keep going back to, that's when it becomes tricky for the actors because now it's like there's no door," Wood said. "You have to come this way and go around here, and you're going around little tiny pieces of green tape on the floor."

Eventually, however, "You don't feel like you're standing in front of a green screen," Tapping said. "You actually feel like you're in the catacombs under Rome or on an island off Scotland. We go everywhere. Once you get used to it, it doesn't feel like you're on a

sound stage anymore."

And that may be the greatest advantage to the technology. The show can go on location — to any location in the world — without actually going anywhere.

"We go everywhere, but we never actually roll trucks and go on location, which is really neat," Kindler said.

"One of the many amazing things about the show is just that — the limitless possibilities that the green screen affords us," Dunne said. "We can go anywhere, like Amanda said. To Rome. To the Bermuda Triangle."

No television series can travel from continent to continent to film episodes. At best, shows are either shot in a specific location — most often New York or Los Angeles — or shot in places like Vancouver, which is made to look as much like different places as possible.

But using the latest technology, anything is possible.

"The real joy of green screen, for me, happens not on the stage but in the story room where fundamentally as a producer, writer, storyteller, you're not bound by what you can build but only by your imagination," said writer/executive producer Sam Egan.

If you watch

What: The new TV series "Sanctuary"

When: The two-hour premiere airs at 7 and 9 p.m. One-hour episodes air Fridays at 8 and 10 p.m. beginning Oct. 10.

Channel: Sci Fi Channel

---

E-mail: pierce@desnews.com