Deep Focus

Deep focus is a cinematography technique that keeps objects in the foreground, middle ground and background of a shot all in sharp focus at once, rather than isolating a single plane of focus and letting the rest of the image blur. It is achieved through a combination of a small lens aperture, which increases depth of field, strong lighting to compensate for that smaller aperture, and wide-angle lenses, and it requires careful staging of actors and sets at different distances from the camera so that action at every depth remains legible. The technique is most closely associated with cinematographer Gregg Toland's work on Orson Welles's Citizen Kane (1941), where it let the director stage dramatic action simultaneously at several distances from the camera within a single continuous shot rather than cutting between separate close-ups.