Long before Photoshop and other image-editing tools, artists, photographers, and composers were manipulating images. We still live in a culture and world where we want to assume that cameras provide us with an "objective truth."
Take, for instance, Dorothea Lange's famous, iconic photograph: "Migrant Mother" is a symbol of Dust Bowl depression and family strength in the face of incredible adversity. However, if we pan back a bit and look at all of Lange's photos from that particular shoot and if we question the way Lange and her crew staged the photo, there's some added detail to attend to.
For instance, both of the other children were laughing and playing. Lange posed the children with their heads behind their mother's shoulder to cover their gleeful faces and create a more somber photo. The mother's hand was deliberately posed to create an air of concern and pondering.