John Knoll's first contact with Industrial Light & Magic began with a hotel phone book.

Already a fan of "Star Wars" and special-effects movies, the high schooler was on a family trip to Anaheim in 1978. Knoll cold-called the company from a white pages listing, identified himself as a model builder, and his father drove 45 miles the next morning to drop his son off in Van Nuys for a tour.

"They were maybe a little surprised I was 15," Knoll recalls. "I went to the model shop and saw what they were building - they were working on the 'Battlestar Galactica' TV series - and on to the stage where they were shooting. It was a fantastic experience that had a huge effect on me. I left that day really determined. 'This is what I'm going to do. I'm going to be one of these guys.' "

Knoll is ILM's visual effects supervisor on "Pacific Rim," opening this Friday. Earlier this year he was named chief creative officer of the company, based in the Presidio. The promotion was another milestone in an eventful 35-year journey for the artist, who co-invented Photoshop with his brother Thomas while working nights at ILM- then walked away from a software career in favor of visual effects.

'Ultimate Renaissance guy'

"He's amazing. He's the ultimate Renaissance guy," says ILM's Hal Hickel, an animation supervisor who partnered with Knoll on "Pacific Rim" and the "Pirates of the Caribbean" movies. "John is highly technical - he comes from a very scientific family. But he also has an amazing eye. He's that perfect example of the visual effects supervisor. He has that balance of the creative and the technical."

Knoll was born to a nuclear engineering professor at University of Michigan - that family trip was for a Society of Nuclear Medicine conference - and got an equal dose of science and art growing up in Ann Arbor. One strong influence was a 1970s film cooperative, which presented year-round screenings of movies that were unlikely to show up on television.

"That's how I saw 'The Texas Chainsaw Massacre,' " Knoll says. "It was rated R. I was 13 or 14 years old. They were loose about that sort of thing."

Skipped engineering school

But it was Knoll's trip to Van Nuys that cemented his goals. (ILM was in the San Fernando Valley before George Lucas moved the shop to the Bay Area to make "The Empire Strikes Back.") Instead of a path working with engineering or computers, he entered USC School of Cinematic Arts.

Being surrounded by aspiring filmmakers didn't stop Knoll from tinkering. He worked as a model-maker on weekends and vacations, and built his own motion-control camera. Knoll was hired by ILM in 1985, and his first film project was "Captain Eo." Immersed in a workplace with like-minded geeks, his interests wandered.

"I had a long history of taking hobbies and making them professions," Knoll says. "When I was a kid one of my hobbies was as model-maker. ... I took up motion control as a hobby, then got hired here to do that. So my new hobby became computer graphics."

During a presentation of the Pixar Image Computer, a graphic design computer developed at Lucasfilm, Knoll became obsessed with the potential of computers to manipulate and enhance photographic images. He fine-tuned versions of Photoshop with his software engineer brother Thomas during the day, while working as a camera operator on the ILM graveyard shift for films including "Innerspace" and "Star Trek IV."

'We should sell this'

"Finally I said, 'We should sell this. I think it has commercial potential,' " Knoll says. "Tom didn't believe me. His first reaction was 'You're crazy. Do you know how much work writing a commercial application is?' Thank goodness I didn't. I was full of naive optimism. I said, 'If you write it, I'll figure out how to make money with this.' "

Thomas did the programming, and John used his afternoons off to shop the program in Silicon Valley. Both brothers worked out of their apartments. Adobe launched Photoshop in early 1990. Married with two children and a third on the way, John Knoll had to choose a career.

"At that point, there just weren't enough hours in the day," Knoll says. "Something had to go."

Knoll returned full time to special effects in 1994, and became one of the studio's most successful visual effects supervisors, working on the three "Star Wars" prequels, two "Mission Impossible" movies and winning an Academy Award in 2007 for his work on "Pirates of the Caribbean: Dead Man's Chest."

Knoll now has the same job title as Pixar animation pioneer John Lasseter; ILM, like Pixar, was acquired by Disney. But Knoll's manner is less Willy Wonka-ish and more professorial. He wears running shoes and a blue collared shirt, and there are few toys in his office. Knoll's idea of fun: He's been salvaging ILM's old computer hardware, restoring the obsolete faceplates to duplicate their original look and lighting patterns.

Knoll also lights up when he talks about "Pacific Rim," ILM's first collaboration with director Guillermo del Toro. The movie is a special-effects artist's dream: a big-budget summer film with an acclaimed director, featuring giant robots defending the planet against invading aliens.

"I've been lucky enough in my career to have opportunities to revisit things that meant a lot to me in childhood," Knoll says. "'Pacific Rim' for me was a chance to touch on those old Toho monster movies. Godzilla and Rodan ... and then Ultraman and Robotech and all those kinds of things. This is a well-made Western production that's a love letter to those kinds of films. We pursued the project vigorously, and we had a lot of fun with it."

Lots of competition

Knoll becomes chief creative officer during a difficult time for the visual effects industry. Two effects companies have declared bankruptcy in the past year, while smaller shops have downsized or closed.

"There's tremendous downward pressure on the prices, with Canada and Australia and New Zealand and Great Britain all offering enormous tax subsidies," Knoll says. "Trying to keep a business like this afloat in California is very hard."

But he doesn't regret staying with ILM - a destiny he says was set during that 1978 tour.

"I set goals for myself that I hadn't accomplished yet," Knoll says. "I wanted to be an effects supervisor on a big film, like a 'Star Wars' film. I felt like I had unfinished business here."

The Big Event: On Peter Hartlaub's blog: ILM's Hal Hickel talks about "Pacific Rim," and a 1978 childhood letter to Lucasfilm that helped shape his career: http://blog.sfgate.com/thebigevent.

Peter Hartlaub is The San Francisco Chronicle's pop culture critic. E-mail: phartlaub@sfchronicle.com Twitter: @PeterHartlaub