Cinematographic

Depth of field and focus

In Citizen Kane (1941), cinematographer Gregg Toland and director Orson Welles used tighter apertures to create every detail of the foreground and background of the sets in sharp focus. This practice is known as deep focus. Deep focus became a popular cinematographic device from the 1940s onward in Hollywood. Today, the trend is for more shallow focus. To change the plane of focus from one object or character to another within a shot is commonly known as a rack focus.