Agent Dave Brolan said Feinstein, who lived in Woodstock, suffered various ailments and was hospitalized with an infection.
Feinstein's best known images include the picture of a skinny, side-glancing Dylan on the cover of 1964's "The Times They Are A-Changin"' and of Harrison sitting among garden gnomes on his 1970 solo album, "All Things Must Pass." But Feinstein had varied experiences that ranged from working as an assistant at Columbia Pictures, photographing Hollywood stars like Steve McQueen and Judy Garland and later shooting rock royalty of the 1960s and 1970s. He also made films.
Feinstein was friends with Dylan's early manager Albert Grossman. Brolan said the photographer got to know the rising music star on a long ride from Denver to New York to deliver a Rolls Royce to Grossman.
Feinstein's pictures gave an insider's view of Dylan's world. One well-known shot shows Dylan, with dark sunglasses and cigarette, in the back seat of a limousine with fans pressing their faces against the window.
Feinstein branched out to other rock work, shooting album covers for Janis Joplin's "Pearl" and for Eric Clapton, among many others. Despite his proximity to big stars, Brolan said Feinstein never betrayed their confidence.
"Barry would never tell you about anyone. He'd never tell you a Dylan story or anything personal. He would never talk about himself," Brolan said. "It was a hard push to get him to say anything about his work. He'd just say, `Look at the pictures, good luck."'
"Hollywood Foto-Rhetoric," a book of Feinstein's evocative old Hollywood pictures and poems Dylan wrote in the early 1960s to accompany the images, was published in 2008.
Feinstein's still photographs were used in Martin Scorsese's documentaries on Dylan and Harrison.
He is survived by wife Judith Jamieson and two children from previous marriages.