With the Bedford Gallery's new exhibition "Broadway Revealed: Behind the Theater Curtain," 360-degree nature photographer Stephen Joseph is headed indoors.

Known for his panoramic capture of the outdoors in books on Contra Costa's Mount Diablo and the John Muir National Monument in Marin County, Joseph gained access to the inner sanctums of Broadway's top lighting, costume, sound and set designers.

The exhibit is part hometown love affair -- Joseph grew up in New York City, where his mother still attends Broadway shows -- and part voyeur's dream. After all, who wouldn't leap at the chance to poke around in the closets and vestibules of designers William Ivey Long ("Chicago"), Donald Holder ("Spider-Man") or Santo Loquasto ("Grand Hotel: The Musical") or gain access to such blockbuster shows as "American Idiot?"

"This all started with my mother," Joseph said during a pre-exhibit tour, as the show was being mounted. "And when (costume designer) Marjorie Bradley Kellogg agreed to participate, it just took off."

His description sounds easy, like the fabled story of an unknown discovered at a drugstore soda fountain. It's an impression he is quick to correct.

"The planning, arranging, scheduling with these folks is hard. Willa Kim took two years," said Joseph, referring to the Tony-winning costume designer. "These people travel all over the world, and I would go every couple of months over a two-year period to photograph."

There were other obstacles. One woman had her assistant spend days cleaning up the studio before Joseph arrived.

"I walked in and said, 'This is too clean. Messy is good!' She had her assistant remess it up before I shot the pictures," Joseph, said, laughing.

Using a Nikon D800, he took an average of one hour to shoot the 360-degree studio and stage images.Joseph explains the process involved for the photograph of "Hair," a swirling splash of color and unexpectedly delightful asymmetry he shot during a performance.

"My strongest compositional element is picking my spot to set up my tripod," he said. "To get a full circle, I take eight separate vertical photos. This means many photos in each position, anywhere from 10 to 100, so I get the best exposure in each layer. Then I stitch them together into a continuous image with Photoshop."

Deciding where to blend, how much distortion to allow, controlling the flattening effect of a round object in a flat format -- these are the master craftsman moments that Joseph handles instinctively after decades of experience.

"He's in complete control of the medium, and this style includes so many details you would not encounter in one view," Bedford curator Carrie Lederer says. "The engaging bravado of Broadway jumps off the canvas."

And it tells a surprisingly touching story. These photos depict the "unknowns" behind the massive machinery that is a Broadway show. Bringing them into the spotlight pays homage to their influence.

"Let's say you go to 'Wicked,' " Joseph says. "It's a spectacle, an illusion. No one thinks how it's formed. With this, you come away with a feeling for the great melding of talents in theater."

The biggest surprise for Joseph -- and likely, for gallery visitors -- is the number of big-name designers willing to throw open their doors to scrutiny. The exhibit is a who's who of insider's fame.

The photos also reveal some hard-to-notice gems when studied up close: the "Pierce Brosnan" label on a wig head; the cat (name: "The Chicken") sprawled across costume designer Suzy Benzinger's sketches; or the famous red stairs caught inconceivably void of people in "Times Square."

"Those stairs are never empty," Joseph says. "There were 200 people around me! When they'd step aside, I'd snap a shot."

This is hardly the final curtain for the exhibit or Joseph's love affair with the subject. He continues to add to the collection, which includes loaned artifacts and an entire room devoted to "American Idiot," the jukebox musical co-created by the East Bay band Green Day, which premiered in 2009 at Berkeley Repertory Theatre.

The exhibit travels to the New York Public Library for the Performing Arts in Lincoln Center in February, but don't be surprised if it resurfaces in the Bay Area in one form or another.

Joseph is working with Lederer and others to find additional venues for the exhibit, and he's also seeking a publisher for a book deal.

'Broadway Revealed: Behind the Theater Curtain'

Photographs by Stephen Joseph

Through: Feb. 17
Where: Bedford Gallery at Lesher Center for the Arts; 1601 Civic Drive, Walnut Creek
Tickets: $3-$5; free first Tuesday of the month, free to ticketholders of Lesher Center events; 925-295-1417, www.bedfordgallery.org.
Reception: 6-8 p.m. today at the gallery; $5.