That is precisely the definition of emphasis. In art, emphasis consists of an object or content that draws attention to itself, becoming a focal point, a dominant element. In order to do so, the other elements (in the picture, photo, etc.) are minimized or toned down. An example of emphasis can be found in Francisco Goya's painting "The Shootings of May Third 1808", where the focal point is much brighter than the other elements.
