Guinevere

Connie, an aging Bohemian photographer, meets mousy Harper, headed for Harvard Law from a high-powered San Francisco family, and immediately sees her beauty. He also guesses she has talent and invites her to be his pupil and share his bed. He's Alfred Stieglitz, she's Georgia O'Keefe, and he calls her his Guinevere. When she realizes she's the latest Guinevere in a string of ingenues, she bolts, only to return, sick of her family... (imdb)