Back in 2015, as London-based portrait photographer Benjamin McMahon was building his career, his mentor, photographer Julian Broad, gave him a valuable piece of advice: “Don’t start changing your style. Just get on with what you want to do and make the pictures you want to make. The right people will come to you.”

McMahon took him at his word, and soon began shooting regularly for British Vogue, Vanity Fair, and several of the British newspapers. But making the pictures he wanted to make was often challenging: many of his celebrity sitters were short on time, needing to be whisked away almost as soon as they arrived. In the hurried minutes at the end of a shoot, McMahon frequently found himself with too little time to create a picture he was happy with, but he also did not want to wrap early and waste an opportunity.

He soon got to thinking about how he could use the time to create something that was true to his style. Then he hit upon an idea. “I was getting frustrated about only having a short amount of time one day,” McMahon explains over a peppermint tea in London’s Tate Modern. “So, I figured, it would be interesting to see what happened when I let the sitter [make the picture] instead.”

He would ask each person for one last photo—one they would take in a mirror, directed and curated by him. With all the planning—location, angle, lights—sorted in advance, the shot would take no more than ten minutes (though sometimes less).

In the five years since he began the series, titled “Not Myself,” McMahon has directed self-portraits by the likes of Judi Dench, Gillian Anderson, Terry O’Neill, Fabienne Verdier and Peter Blake. McMahon recently exhibited the work at London’s Elephant West, the gallery arm of contemporary art magazine Elephant.

When he’s working with his subject on a self-portrait, McMahon shifts the dynamic of the shoot. He guides his sitter, opening them up, so that the resulting partnership yields a very different portrait than we are used to seeing in the pages of magazines. When he began the series, “I hoped that people would give something different to the project because they were giving it to themselves, not me,” he says. By handing the camera back to the sitter, McMahon gives his subjects a quiet freedom. It’s a very personal process.

What began as a “silly extra thing,” has grown into something more significant. Touching on the ideas of ownership and the photograph as an art form, the series is also a fascinating exploration of the bond between shooter and shootee and the trust needed to create a truthful photograph.

He finds his stripped-down setup—it’s usually just him, his trusty Leica M and maybe an assistant—puts people at their ease. “But it has gone down like a sack of hammers as well,” he admits. “People say where are your lights? One fashion PR [agent] was so insulted that I hadn’t brought anything with me [to photograph her]. But then afterwards she bought a print.”

McMahon, who was featured in PDN’s 30 in 2015, seems amazed that anyone wanted to come and see the exhibition, but the self-portraits have piqued people’s curiosity. On opening night, the gallery was packed. But say the word “artist” instead of “photographer” to McMahon and he screws up his face. He hates that idea, but that doesn’t mean he doesn’t admit to the odd “weird artist” moment.

On one occasion, he fell out with a famous author over a portrait he was sent to shoot for a national newspaper. “We were both being egomaniacs,” he admits. They eventually settled things amicably, so much so that McMahon has photographed the writer several times since.

Another time, he was sent to photograph Primal Scream frontman Bobby Gillespie, but the singer didn’t like McMahon’s concept for the shot. There were no cross words this time. “I said, ‘I like your music and I don’t want you to think I’m a prick, so let’s just sack it off.’” The duo ended up going for a walk before shaking hands and parting ways. Not long after, Gillespie’s PR [rep] came running after McMahon, saying the rock’n’roller would do it. “I said, ‘Look, there’s only one picture I want to make, and I get he doesn’t have to do it.’”

McMahon got his shot, plus a self-portrait for “Not Myself” too. It seems he often wins over his subjects in this way, ironically just by being himself. He admits, “The nicest thing anyone ever told me on a shoot was that they forgot I was taking pictures. I loved that.”

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