(CNN) The story of photographer Jill Freedman starts with a man on a mule. It was 1968 in New York's Central Park. The man had worn coveralls to the big city, and he talked of revolution.

"I may be poor, but I am somebody," he told her. He was part of the Poor People's Campaign, a movement for economic justice conceived by Martin Luther King Jr. and carried out by impoverished Americans of all races.

Join us, the man said -- and Freedman answered with her whole being.

She quit her job as an advertising copywriter and marched to Washington to live among the plywood shacks of a hasty shantytown erected on the National Mall.

Her boots and sleeping bag were stolen the first night. It rained every day. She bulk-loaded film while eating bologna sandwiches and peeing into chemical toilets that had no chemicals. She photographed continually for six weeks for no one but herself and her muddy comrades. It was glorious work, but not paid. That was fine by Freedman.

"If I had an assignment, I would have been in a hotel, I would have had food -- I wouldn't have been part of it," Freedman said. "That set my way of working."

Photographer Jill Freedman

Freedman needs to be inside the story to tell it. For her 1977 book "Firehouse," the documentary photographer spent more than a year sleeping in the back seat of a fire chief's car at various firehouses in New York. As a woman, she wasn't allowed to sleep in the firemen's dorm, but she was determined to live side by side with them.

The results of this immersion are images that describe a community of men in their full humanity, heroic but not just heroes. Pictures of terrible danger meet moments of rough tenderness, then all gives way to goofball antics back at the station. Freedman wasn't interested in profiling her subjects. She was out to author their story, long-form.

"I chose to tell stories with the camera," she said, and often those stories are about how society doesn't work for a lot of people. At the height of her career, Freedman came alive walking the fringes of New York in the '70s and '80s, through alleys and hallways where the rules had ceased to make any applicable sense. Armed with beat-up Leica M4 cameras, her reputation as a fearless street shooter grew.

For her 1982 book "Street Cops," she talked her way into another back seat -- this time riding along with New York's Finest.

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"I had never seen a book about good cops," Freedman said. "I got thinking, I hate cops -- but wait a minute, that's a stupid thing; I don't know any cops." She wondered: What does it mean to be a police officer every day?

It meant ugly scenes of violence and despair. Beatings, blood and everyday agonies. A continuous sifting of the signals around you: Is this a good guy or a bad guy? What's down those stairs? Freedman set out to strip any Hollywood glamour from the police beat. Instead, she told a story of constant vigilance lit by flashbulb moments of lives crumbling.

There was a price for living so deeply within the stories she told. Though her work is archived in such lofty permanent collections as the International Center of Photography and the Museum of Modern Art, Freedman's career never fulfilled the potential critics once predicted. Those who know her work compare it to luminaries like Mary Ellen Mark , Joel Meyerowitz and Bruce Davidson, but more often, her name simply goes unrecognized.

"I'm just not a good hustler," she said. She'd always worked on self-assigned, book-length projects, rarely taking paid assignments.

I wanted to tell stories, and if nobody would send me, I would just go. Photographer Jill Freedman

"I wanted to tell stories, and if nobody would send me," she said, "I would just go."

Time spent schmoozing for work was time away from the story. "So there was a choice: Hustle and make a name for myself, go to all of the right places and hobnob and say stuff you don't mean, or continue worrying about the rent," she said.

In 1988, Freedman was diagnosed with breast cancer. She had no health insurance and no steady means of income. Though her treatment was successful, it drained her physically, financially and creatively.

She moved away from her beloved New York, embedding herself on a beach in Miami to read books and swap stories with strangers. Her work faded from the photography scene, and some even thought the cancer had killed her. It was a period of "living without living," she said.

Yet she kept taking photos. "Every now and then I'd make a new picture and I'd get excited," she said. She missed New York terribly -- "the wise-cracking and the food" -- and in the mid-2000s she moved back to find the city she loved had disappeared.

"There's no more Greenwich Village," she said, at least not the one she knew. "That was my neighborhood, which is gone."

The junkies and prostitutes were also gone from Times Square, and the tourist-bait set that replaced it sent her into tears. Disoriented, she floated between temporary homes. "For a long time I really didn't know what I was doing. I wasn't really into it," she said.

But here's where her story rallies. After finding a permanent residence in 2007, Freedman gathered 40-plus years of photographs, much of it shot in the New York she remembered. That New York -- the grimy, crime-filled city on the edge of disintegration -- was yet another story she'd lived. There was an idea in that.

Now 75, Freedman is determined to claim her place next to her better-known contemporaries. The fiery spirit that sent her plunging into the streets still urges her to wander in search of more stories.

"I don't consider that I've really had a full life so far, because I spent a lot of time sitting on my rear end," she said.

For its part, New York hasn't forgotten Freedman, either. A retrospective of her work, "Jill Freedman: Long Stories Short," opens at the Steven Kasher Gallery on September 17, where photos of firemen and police officers will mingle with circus clowns, dogs and other subjects from the seven books she's published. Her next book, tentatively named Madhattan, awaits a publisher.