The documentary 'The B-Side: Elsa Dorfman's Portrait Photography' by Errol Morris will be screened at Music Box Theatre in New York from July 11 through July 20, 2017.Elsa Dorfman is an American portrait photographer who works in Cambridge, Massachusetts. She is now known for her use of a large-format instant Polaroid camera. She found her medium in 1980: the larger-than-life Polaroid Land 20x24 camera. For the next …