Saturday Special: Citizen Kane (1941, Orson Welles) is famous for cinematographer Gregg Toland’s innovative use of deep focus techniques. In this scene, which might conventionally be told in three shots (a close-up on the medicine bottle, a medium of Susan on the bed, and then a wide of Kane entering the room), all three planes remain in sharp focus through the use of a matte shot. The extreme foreground was shot first, with the rest of the scene dark, then the film was rewound and only the middle-ground was lit and shot, and the same for the background. Many special effects in early films, like those of Georges Méliès, relied on this multiple exposure technique; the disadvantage is that if any of the takes went wrong, the whole process would have to start again.
The result is one of the most striking images in a film full of striking images.