New York ? Annie Leibovitz is sitting in her Greenwich Village studio, watching her life flash before her eyes.

Fifteen years of it, to be precise, the part she’s collected in her new book, “A Photographer’s Life: 1990-2005,” whose 472 pages her visitor is flipping through now. It’s a startling compilation, including as it does both previously unseen images of her family and her companion, Susan Sontag – who died in December 2004, just weeks before Leibovitz’s father – and the trademark portraits that shout out to celebrity worshipers from the pages of Vanity Fair.

Different planets? Not to the photographer. Yet the private and the public work – and the way Leibovitz talks about them – can feel shockingly at odds.

Personal and professional

Take this close-up of a rippling, naked torso: It’s Sylvester Stallone’s. “I like him better without his head,” she says, explaining the simple Hollywood concept behind the 1993 shot. “He was selling his body.”

Now take the nude on white sheets, pillow partially covering her chest, shot the following year. This is Sontag, who’d had a radical mastectomy during her first bout with cancer. “I think she felt like she wasn’t beautiful – and I thought she was beautiful,” Leibovitz says.

She calls the photograph “one way to show my love.”

Flip, flip, flip. More pages turn.

Here’s an extended family cavorting at the beach; an intimate moment in a Venetian hotel; a pregnant actress, naked save for the humongous jewels ornamenting her hand and ear. Here are birth and death, artifice and performance, love and loss – everyday human drama juxtaposed with the theatrical excess that celebrity culture demands.

Leibovitz doesn’t much like the term “celebrity,” at least when applied to her day job. She calls herself a portrait photographer, which at least sounds dignified, and talks about the blend of “assignment work” and “personal work” that makes up the new book. Both elements were needed, she says, because “I don’t think they were strong enough without the other.”

Still, there’s no doubt which genre she thinks is the most important right now.

As she told the overflow crowd crammed into a Washington bookstore on Monday, putting the book together helped her grieve. She choked up momentarily as she read the last line from her introduction:

“It’s the closest thing to who I am that I’ve ever done.”

‘Raising the bar’

Who she is this day, on the surface at least, is a nearly 6-foot-tall, 57-year-old whirlwind wearing jeans, hiking boots and a black V-neck top over a green tee. She carries herself with the confidence of a strong woman used to lugging heavy camera equipment through five-star hotels.

On the evidence of her connection with the famously intellectual Sontag, she’s a good deal more complicated than a stereotype like “imagemaker to the rich and fabulous” might suggest.

The two women met in the late 1980s, when Leibovitz did some publicity shots for a Sontag book. They shared a love of travel, and without the writer’s energetic activism, the photographer would never have made it to besieged Sarajevo, Bosnia, in 1993-94 – where, telling herself at first that she was qualified only to shoot portraits, she ended up with some striking reportage.

“When I met Susan, how could I not imagine that it was this opportunity for the work,” Leibovitz says. Here was the author of “On Photography” telling Leibovitz she was good but could be better. “That was just raising the bar for me.”

Bizarre juxtaposition

“A Photographer’s Life” began with Leibovitz digging through old pictures to put together a little book for Sontag’s memorial service, finding images she didn’t know she had.

She’d signed a contract with Random House for a collection that was to cover the years from 1990 to 2005. These were the years she’d been with Sontag. She began to think of combining her personal and public work.

“I did the edit as if this is the photographer I’d like to be,” she says. “I took the assignment work and the personal work and made it the same size, and I was floored with how it worked: Everything was sort of made democratic.”

She points out some of the effects that the project created. For example: “Here was suddenly Sarajevo next to Brad Pitt.”

But that kind of bizarre counterpoint was actually happening in her life. She’d go to Sarajevo, shoot a baby being born, without anesthesia, during the siege; shoot a bloody smear on the road where a boy had been blown off his bicycle – and the next thing she knew, “I had to remember which side to shoot Barbra Streisand’s face from.”

It could be anyone’s story, anybody’s family album. Ah, but then you inject “Bush, Clinton, Arnold Schwarzenegger, Nelson Mandela.” Leibovitz’s personal narrative, Holborn says, is populated “by people who populate all our lives.”

Best work

Flip, flip, flip. Sometimes the blur is like a montage of the pop culture dreamscape, a world where we’re invited to call everyone – Bruce, Hillary, Quentin, Vanessa, Nicole, Susan – by their first names.

Yet there are hints that Leibovitz is tiring of the performance part.

Over and over, she’s been telling interviewers: This is the best work I’ve ever done. It’s clear she doesn’t mean the nude shots of Demi Moore.