This handsome volume offers an innovative perspective on the artistic processes of some of the most influential photographers of the 20th century. For decades before the advent of digital technology, the proof sheet or contact sheet was vital to the practice of photography. Photographers using roll film first saw positive images in the small-scale grid of the contact, which was marked for printing and served as a lasting reference. Because contact sheets typically remained out of view, they offer a privileged window into the working process. Photographers also recognized aesthetic potential in the proof sheet itself and occasionally presented the contact grid as a finished work of art. The lively but largely unexplored territory of the contact sheet is richly represented in the previously unpublished collection assembled by Mark Schwartz and Bettina Katz. As he charts this territory, Peter Galassi offers fresh insights into the work of Diane Arbus, Richard Avedon, Harry Benson, Harry Callahan, Larry Fink, Robert Frank, Emmet Gowin, Philippe Halsman, Arnold Newman, Irving Penn, and others.