A box of old photos has kept American photographer Bill Delzell busy for more than four years, and now 75 rolls of unprocessed film from a Saskatchewan lab may help him identify the person who shot them.

Sometime in the 1960s, an unknown man or woman moved through San Francisco photographing scenes from the decade, including Muhammad Ali on stage burning a draft card, a young Carlos Santana bent over his guitar, and images of the counterculture with flower-painted vans and signs for peace, love and freedom.

“When I saw the work, I only turned a few pages of these albums and I felt like I’d seen enough. I had this sort of powerful emotional feeling about it,” said Delzell, who lives in San Francisco.

A collector first showed him the photos and told him they had been found abandoned in a Bay Area storage locker in the 1980s.

“I just felt like, what a tragic loss, this notion that someone could have devoted that much time and then walked away. There had to be a story behind that.”

Delzell has spent years trying to identify the photographer and work out how that person got so close to so many moments in San Francisco history.

“We have since found footage from other news outlets that shows a mysterious figure wandering through the crowd. And we think that’s our person,” he said.

He bought the collection and also acquired 75 rolls of unprocessed film that he hopes could offer more clues.

“As a photographer, I knew that film sort of expires over time,” he said.

Delzell worried the film may have been exposed to heat or light, and said it needed careful development.

“So I knew I needed to find an expert.”

He found that expert at Film Rescue International in Indian Head, Saskatchewan. To avoid airport X-rays, he drove 25 hours to the town with the film.

In an old bank building there, film archivist Gerald Freyer works on old cameras and rolls of film for people from around the world who want help developing aged film.

“I need a bell for each amazing picture, and I should ring that bell nearly three, four times a day when I’m digitizing,” Freyer said. “It’s like watching The History Channel all day long, you know, because we have these amazing jobs.”

The work on Delzell’s collection will cost tens of thousands of dollars, but it is not the largest project the lab has handled. Film Rescue International has also processed and digitized thousands of photos by late American photographer Charles Daniels, including images of Rod Stewart and Mick Jagger on planes and in hotel rooms.

Film Rescue International’s work astounds Delzell.

“The devotion that it takes to do this kind of work , it’s far beyond the imagination, really,” he said.

Delzell has followed internet tips, shared the photos widely, and raised money to support the project.

In one case, he sent five photographs from the collection to a friend, who said she saw herself as a five- or six-year-old child in one of the images during a march.

Fellow photographer Michael Zagaris also appears in a picture with Ali, who asked him for his draft card and then burned it on stage, according to Delzell.

“Some might call [these] coincidence, some might call it synchronicity,” Delzell said. “I am not looking for an explanation. I’m just continuing the search.”

Delzell lived through the 1960s and said people tend to overromanticize the period. He remembers the decade’s anger over the Vietnam War and racial injustice, and said he was 10 when he went to his first anti-war protest with his father in 1967.

“I distinctly remember him saying, ‘I’m going to send you to Canada if you’re ever drafted. And here we are!'” Delzell said, chuckling.

Now he is relying on the Saskatchewan company as he keeps trying to identify the photographer behind the collection.

“It’s a Canadian treasure.”

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