THE B-SIDE: ELSA DORFMAN’S PORTRAIT PHOTOGRAPHY (Errol Morris). 76 minutes. Opens Friday (June 23). See listing. Rating: NNNN 

Errol Morris’s latest character study is a profile of Boston photographer Elsa Dorfman, whose large-format Polaroid images are so intimate and vivid that they practically seem to breathe. Now in her late 70s, she’s a wonderful subject, discussing her career and work with a matter-of-factness that belies her position in history. The close friend of Allen Ginsberg hung out with the beats in New York and captured some iconic images of a skinny folksinger named Bob Dylan.

But The B-Side isn’t about the famous people Dorfman has known. Clearly spurred by the wane of traditional photography and the demise of Polaroid, Morris is meditating on the impermanence of the image and the inexorable march of time. The film is suffused with an awareness of mortality. 

Not that his subject acknowledges it. Short-circuiting her own self-seriousness and using food metaphors to explain her theories of art, Dorfman gives The B-Side life and energy. She’s giggling against the dying of the flashbulb.