Brian De Palma is known for his use of the split diopter shot, a technique that keeps both the foreground and background in focus at the same time. Achieved with a half-convex glass placed in front of the lens, the diopter makes one half nearsighted and the other farsighted. The effect only works when the camera and actors stay mostly still, creating a sense of stillness and unease. It shows up in Blow Out, Mission: Impossible, Carrie, and many more of his films, often used to heighten tension and draw attention to two competing spaces in a single frame. #BrianDePalma #Movies #MovieClips