Understanding the DM
What he was talking about was only one type of shooting: call it journalism, documentary photography, spot news photography, interpretative or environmental portraiture – even snapshooting.
Cartier-Bresson was talking about photography of the evanescent, of the here and now. The kind of photography that, in many ways, defines the entire craft, the entire art.
Most photography, but especially this kind, has a tenuous reputation for truth-telling largely because of the camera’s, if not always the photographer’s, ability to record events objectively. In fact photography is unique among the visual arts, not only because a photograph cannot be created from (sometimes clouded or prejudiced) memory, but because the subject of the photograph – and not really the photographer – determines absolutely what that depiction will be.
That is to say, Richard Avedon may trip the shutter when he makes a portrait, but the subject’s face and surroundings are what actually burn the image onto the film. Of course, Avedon brings hugely important elements into the equation as well: his talent for composition, for lighting, and of course, his sense of when his subject’s expression becomes, for Avedon, “the picture.”
~Fra nk Van Riper from his article Creating The Decisive Moment