Deep Focus is a cinematographic technique in which both the foreground and background elements of a scene remain in sharp focus simultaneously, allowing the audience to see action and detail across multiple planes of depth within a single shot. It creates a visual field where everything from the nearest to the furthest objects is rendered with clarity, making spatial relationships and layered action visible without requiring cuts or focus shifts.

Achieving deep focus requires a combination of wide-angle lenses, small aperture settings, and strong lighting to maintain sufficient exposure with reduced light transmission through the narrow aperture. The technique was pioneered in classical Hollywood cinema, most famously by cinematographer Gregg Toland in Citizen Kane, where deep focus compositions allowed Orson Welles to stage action across multiple depth planes and let the audience choose where to direct their attention within the frame. Deep focus compositions tend to feel more observational and objective than shallow focus, which isolates subjects and directs attention more forcefully.

In AI image and video generation, specifying deep focus in a prompt helps models understand that all elements in the frame should remain sharp rather than applying selective focus or depth-of-field blur. This is particularly useful for architectural visualization, landscape scenes, or any content where spatial relationships across depth need to be clearly readable.