BY KAREN BOSSICK

Stephen Wilkes has spent the last 17 years standing in one place for 24 to 36 hours at a time, watching the world unfold before his lens.

The renowned photographer's breathtaking "Day to Night" series, which captures the passage of time in a single frame, is now on exhibit at Gilman Contemporary, 661 Sun Valley Road, in Ketchum. And the National Geographic Explorer who is considered one of America's most iconic image-makers will be present for the Gallery Walk from 5 to 7:30 p.m. tonight--Friday, Aug. 7.

The concept began way, way back in 1996 when Life Magazine commissioned Wilkes to photograph the cast of "Romeo and Juliet" starring Leonardo DiCaprio and Claire Danes.

This picture shot at the Rowe Sanctuary in Nebraska is part of Stephen Wilkes “Day to Night” series.

The set was a square, but the magazine wanted a panoramic gatefold. Inspired by David Hockney's photo collages, Wilkes shot 250 individual images and spent two weeks hand-pasting them together.

When he finished, he realized something remarkable: “In the center of the photograph the actors were embracing, but in the reflection of a 25-foot-tall mirror on the set they were kissing.

"I thought, ‘Oh my goodness, time is changing — that is such an exciting concept," he said. "But I never wanted to do a collage again because I didn't have the patience."

Sixteen years later Photoshop made it possible to revisit the concept. In 2009, a New York Magazine assignment to photograph the High Line park, and he had what he calls “a thunder moment.”

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He couldn't decide between the energy of lunchtime crowds or the spooky nighttime atmosphere, so he called his editor with a radical proposal: "What about if I do day on the south side and, as you move up the west side, it turns to night?"

She said, "Could you do that?"

"I can try," he said.

He created one seamless image, and "Day to Night" was born.

“Sandhill Cranes” is comprised of pictures taken from one site over more than 24 hours.

That first image was so profound it launched a new way of seeing. Wilkes has now completed nearly 90 Day to Night photographs over 17 years, and only two didn't work. "As batting averages go, that's pretty good," he said.

There is nothing automated about Wilkes' work. He stands at a fixed camera position for up to 36 hours, looking and shooting up to 3,000 images as light shifts, shadows move and life unfolds around him.

"I'm about being present and just looking," he said. "It's a deep meditation in a world where we're all connected to iPhones and text messaging. My work is the antithesis of that."

“Huge Toolshed” shows the vastness of Bethlehem Steel, thanks to a man standing at the far end of the building.

His camera is a discontinued studio model never intended for location work — a 50-pound assembly built into the tripod head that gives him the precise control he needs but is so sensitive that breathing on it wrong can throw it off.

At 86 stories, building sway becomes a factor, so he shoots into a computer with a grid system to track any shift and waits for the building to resettle before continuing.

Each photograph takes about a month to edit, distilling thousands of images down to roughly 50 key moments that are seamlessly blended along what Wilkes calls the "vector of time"—the precise point where day begins and night ends.

Over four months, he creates harmony between the discordant worlds of day and night-- sunrise bleeding into midday bleeding into dusk bleeding into night, all in one frame.

"You do not feel the hand in this picture," he said. "There is no hand in this picture."

One photograph required standing in an open-air breezeway on the 86th floor above Central Park at 111 W. 57^th St—one of the tallest residential buildings in the world.

It was like being on a mountaintop, he said, describing how he wore thermal underwear to counter the wind blowing through the breezeway even when temperatures below reached 80 degrees.

"I can't even begin to tell you how cold it was for the winter shot," Wilkes said with a laugh. "That was ridiculous."

His earlier series on Ellis Island's abandoned medical wards helped secure more than $6 million for restoration efforts. His photographs of Bethlehem Steel document the humanity lingering in the empty rooms of a shuttered American industrial giant, the welfare room with all its hangers knocked down 20 minutes after he photographed it.

In the wild, his patience pays off in magical ways. For one image shot over three days, he had zero wind for 36 hours, a full moon, and bears that kept showing up to fish right in his frame. One bear walked into the frame to fish. A cub sat down with its catch, looking directly up at the camera as if on cue. And a kayaker paddled into the picture.

"What I've learned is that my energy is critical to my success," he said. "The more I put out an openness and a sense of respect, that's when things happen for me. My assistants think I have a halo on my head, but I'm just a lucky guy."

His work, he said, allows people to "put a face on time." A National Geographic photo editor once told him his “Day to Night” images are a more accurate representation of a place than a single photograph.

Photography is selective, he explained — one photographer might capture a baby laughing, another a baby crying. In his images, you see the day unfold, the light change, the city lights come on, the fireworks go off.

Most recently, Wilkes was commissioned by New York Magazine to create a "Day to Night" of America 250 in New York Harbor. As he stood in Jersey City looking at lower Manhattan, a massive storm system rolled in from 34th Street north. But everything below him stayed clear. The fireworks went off under perfect skies while the rest of the city got drenched.

"Everybody else got rained out," he said. "I didn't. I paid my dial-a-sky bill."