Peter Henry Emerson, arguably the father of modernist photography, struggled throughout his career to articulate a theory of art for photography. A consideration of key themes in this struggle—including technical decisions about depth of field, choices about how to stage representations of labor, and his use of figures for the frame that sets the photograph apart from the world—reveals that Emerson's theory and practice contends with issues that return to play a central role in debates about the break separating modernist and postmodernist photography.