Deep focus cinematography allows the human eye to choose its own path through a scene

Orson Welles and cinematographer Gregg Toland revolutionized visual storytelling in 'Citizen Kane' by keeping the foreground, midground, and background in sharp focus simultaneously. To achieve this, Toland utilized wide-angle lenses and stopped down the aperture to f/8 or smaller, requiring an immense amount of light—often 25 to 100 foot-candles—to expose the film correctly. This technique broke the Hollywood tradition of 'rack focusing,' where the camera dictates exactly what the viewer must look at by blurring everything else.