Ecological

In the infancy of motion pictures, the cinematographer was usually also the director and the person physically handling the camera. As the art form and technology evolved, a separation between director and camera operator emerged. With the advent of artificial lighting and faster (more light sensitive) film stocks, in addition to technological advancements in optics, the technical aspects of cinematography necessitated a specialist in that area.

Cinematography was key during the silent movie era—with no sound apart from background music and no dialogue, the films depended on lighting, acting, and set.

In 1919, in Hollywood, the new motion picture capital of the world, one of the first (and still existing) trade societies was formed: the American Society of Cinematographers (ASC), which stood to recognize the cinematographer's contribution to the art and science of motion picture making. Similar trade associations have been established in other countries, too.

The ASC defines cinematography as:

a creative and interpretive process that culminates in the authorship of an original work of art rather than the simple recording of a physical event. Cinematography is not a subcategory of photography. Rather, photography is but one craft that the cinematographer uses in addition to other physical, organizational, managerial, interpretive and image-manipulating techniques to effect one coherent process.