A YOUNG BOY who plays with electricity the way most of his friends might toy with Tonka trucks seems destined to head in one of several directions -- one being a career as a mad scientist creating large oafish beings in his dingy lab; the other as a video artist using his knowledge of electricity and digital software to create works of beauty.

Ed Tannenbaum took the latter route. The Crockett artist is collaborating with the Lily Cai Chinese Dance Company for its performances Friday and Saturday at the Yerba Buena Center for the Arts. Wielding long ribbons, the dancers will twirl and leap as their movements simultaneously streak across a 20-foot projection screen like that of a Jackson Pollock painting -- courtesy of Tannenbaum.

In the mid '70s when video was in its early infancy, the 48-year-old says his electrified curiosity led him away from traditional art studies of such time-honored mediums as painting and photography, and redirected him toward video. Tannenbaum was fascinated by the countless ways to manipulate subjects. Since then, he's collaborated with numerous dance companies, stretching the conventional dance repertoire, and hosted installations around the world.

If you've been to the Exploratorium, you've probably been fascinated by his "Recollections" exhibit. Similar to shadow rooms that capture your silhouette on the walls, Tannenbaum's exhibit takes a vibrant step further. Your silhouette is projected onto a large screen, but as you move, your shadow paints rainbow trails. (You're not required to have grown up in the '60s to appreciate it.)

When did you first have an interest in electronics?

"I built my first computer in sixth grade, and a mechanical digital computer in seventh grade. For the first one, I used a cigar box. It was from a little kids' book on how to make computers. I was always interested in electricity, though. One of my first memories is when I stuck a magnet into an electrical outlet. I just remember the beautiful sparks coming out of the wall. But I'm still afraid of it."

And what did your parents think of this fascination?

"They didn't like it, because I was always messing up the color TV, changing the knobs. For years, my mother couldn't figure out what I was doing. She told friends I was a TV repairman."

What in particular drew you to video?

"I loved the immediacy of it. With film, you have to wait for it to be processed and do something to the film, and it's a long and sometimes expensive process to see the results. With video, you can alter an image and see it right after. It's the Polaroid of film."

What was the response from art circles when you began working with video?

"Very mixed. We were sort of enemies of the art studio. Technology was thought of as evil. But all artists use the latest technology of the age. The early artists had to make their own colors; now we have oils."

When did you begin collaborating with dance companies?

"The head of the RISDE (Rhode Island School of Design) video department's wife was a dancer. She introduced us to dance and had the idea of combining dance with video. I guess back then was when I became interested with the idea of using dance and movement with video."

What other dance companies have you collaborated with?

"The most famous was Debra Allen. I did an episode of 'Fame.' They knew about my work with performers and had a script based on that. It was only a few minutes, so it was more like a demo. I had to cram a million effects in a few minutes."

What was it like working with Lily Cai?

"She's got a beautiful sense of color. When she approached me, she said, 'I want to make paintings like Jackson Pollock.' I went and wrote the software. It really allows painting with the ribbons."

What led to your work with the Exploratorium?

"I moved here in '79. My friend was moving out here and it was like, 'Want to take a ride to California?' That kind of thing. I had been working on a project and brought my tape with me. I proposed a project to them and they liked the idea."

Does your work involve a lot of tech-knowledge?

"Yeah. There's a lot of programming involved. I used to do a lot of hardware design. Computers back then weren't very fast. I had to teach myself everything. When I said video was the Polaroid of film, that's not entirely true. It takes a long time to write the software before I can see anything."

Do you still work in other mediums?

"I still do photography, a lot of 3-D photography. When I get totally tired of the technology, I'll probably go back to studio painting."

-- Cassandra Braun

The Lily Cai dance performance runs 8 p.m. Friday and Saturday at the Yerba Buena Center for the Arts, 701 Mission St., S.F. For details, contact 415-978-2787 or http://www.yerbabuenaarts.org/.