Every year since 1974, San-Francisco-based photographer Lucy Hilmer has taken a self-portrait, from Death Valley to the beach to a room in her own home, wearing nothing but her shoes, socks, and a pair of white bloomers. The Huffington Post has published a series of Hilmer’s striking images, from one of the first ones in the 1970s, to one taken a couple of years ago at age 67, and they’re absorbing.

True, our interest in this time-lapse series of photographs of the artist in her “birthday suit” may be heightened at the moment by a recent viewing of Richard Linklater’s film Boyhood, in which the film and all its actors were shot over a 12-year period and the viewer sees the characters age in reality as the film chugs along over nearly three hours. Like the film, these photographs traffic in the effects of time, or, in Hilmer’s words, with the notion that we’re “slip-sliding away, becoming different versions of ourselves before we know it.”

The photographs are strong. They’re specific and surprising in their detail and composition (like the image of the subject nursing her child who is standing on the lap of what looks like the subject’s husband), yet unfettered by concerns that are too personal or local.

“What I’ve learned [from this series] goes far deeper than what can be expressed in a photograph,” Hilmer told the Huffington Post. “But the photograph has been a marker for me, an indication of a deeper truth.”

Take a look. These are worth a gander.