Only once in the 76 years since he first picked up a Brownie box camera as a teenager in Ohio has Pirkle Jones withdrawn his finger from the shutter, reluctantly letting go a photo he desired. "In the ’70s, I saw a fortune teller at a flea market," he recalls. "She said that she’d put a curse on me for the rest of my life if I took her picture. So I didn’t."

By then, Jones, who is now 93, was accustomed to difficult subjects. He’d photographed Southern California ranchers evicted from their homesteads and the Black Panthers under siege. These revealing images owed their technical prowess to his training under Ansel Adams, yet the psychological acuity of his pictures was self-taught, emerging from his compassion for those in front of his lens.

Jones’s integrity is palpable, as is his earnestness. He has the round face and flat accent of a Midwestern farmer. Dressed in a plaid shirt, shorts and knee-high socks, he pads around his Northern California house leaning lightly on a walker, reminiscing about the camera clubs that first showed his finely toned pictorialist compositions in the ’30s, describing how the honorable mentions he amassed bolstered his confidence as a hobbyist. By 1941, when he enlisted in the Army, his photographs had been published and exhibited around the world. "In the back of my mind, I thought I might like to continue in photography after the war," he says, easing into a chair.

The opportunity came in the form of the G.I. Bill and a new department at the California School of Fine Arts, run by a man whose name he’d seen more than once in pictorialist salons. Ansel Adams founded the college’s first photography program in 1946, with assistance from fellow luminaries Imogen Cunningham, Minor White and Dorothea Lange. Instead of returning to his prewar job at a shoe factory in Lima, Ohio, Jones began taking classes in San Francisco. "It was like starting all over again," he says. "I had never handled a view camera, and Ansel was a disciplinarian. Once we were complaining about not having enough time to finish an assignment. He asked how many minutes it took us to shave in the morning."

When he wasn’t goading his students, Adams would take his class to Carmel, where they’d visit Edward Weston, another major inspiration for Jones. "I was impressed by Weston’s environment, the simplicity of his life, quite the opposite of Ansel’s," Jones recalls. Ruth-Marion Baruch, a young student writing her dissertation on Weston (and taking classes with Adams), also impressed Jones, enough that they were married in 1949. "I was attracted to her because she owned half a dozen of Edward’s pictures, and, you know, one thing led to another," he says, momentarily losing his loquaciousness, if not his humor.

Their wedding was in Adams’s Yosemite home. By then, Jones was Adams’s assistant, traveling with him on assignments and printing his negatives. Jones also had his own commercial work, including a job documenting the construction of the Paul Masson winery in Saratoga, California. As the project evolved, the owners of Masson considered a full-scale exhibition. Adams joined Jones as a collaborator, and their combined vision of a vineyard rising up on the California landscape traveled, with acclaim, to the Smithsonian. "People like wine," he says.

A more meaningful project for the young photographer showed the California dream from a rather different perspective, documenting the consequences of relentlessly expansive cultivation: In 1956, Jones and Dorothea Lange traveled to the Berryessa, Valley one year before the U.S. Bureau of Reclamation flooded the farmland to make a massive reservoir. Lange had secured an assignment for Life magazine, and initially asked Adams to work with her. Unhappy with the results of their previous collaboration in Utah, Adams demurred, recommending Jones, whose enthusiasm for the project has not diminished in five decades. "We were working against time," he says, his large eyes widening. "It was a one-shot deal, showing the change, and what it did to people." For 12 months they shot without a preconceived plan, witnessing a graveyard being overturned, houses burning, people leaving. Then the valley was drowned, and Life turned their essay down. "Those magazines, quite often they’d use one story in 10," Jones says, grateful now to have control over the photographs, which he believes have grown in impact. "They become a reference for historians and for people in general."