The choice of shooting format affects how easy it would be to achieve a deep focus look. Thus the viewer is induced actively to participate in the drama planned by the director. Paradoxically, the true action, the one that constitutes at this precise moment a turning point in the story, develops almost clandestinely in a tiny rectangle at the back of the room-in the left corner of the screen. The action in the foreground is secondary, although interesting and peculiar enough to require our keen attention since it occupies a privileged place and surface on the screen. He elaborated in an analysis of how deep focus functions in a scene from Wyler's The Best Years of Our Lives: Filmmakers such as Akira Kurosawa, Stanley Kubrick, Kenji Mizoguchi, Orson Welles, Masahiro Shinoda, Akio Jissoji, Terry Gilliam, Jean Renoir, Jacques Tati, James Wong Howe, and Gregg Toland all used deep focus as part of their signature style.ДЇor French film critic AndrГ© Bazin, deep-focus visual style was central to his theory of realism in film. Other auteurs choose to use it consistently throughout the movie, either as a stylistic choice or because they believe it represents reality better. Directors and cinematographers often use deep space without using deep focus, being either an artistic choice or because they do not have resources to create a deep focus look, or both.Дirectors may use deep focus in only some scenes or even just some shots. Deep space is a part of mise-en-scГЁne, placing significant actors and props in different planes of the picture. When deep focus is used, filmmakers often combine it with deep space (also called deep staging). The opposite of deep focus is shallow focus in which the plane of the image that is in focus is very shallow. It is the aperture of a camera lens that determines the depth of field. It is also possible to achieve the illusion of deep focus with optical tricks (split-focus diopter) or by compositing two or more images together. A wide-angle lens also makes a larger portion of the image appear sharp. Since the aperture of a camera determines how much light enters through the lens, achieving deep focus requires a bright scene or long exposure.

In deep focus, the foreground, middle ground, and background are all in focus.Дeep focus is normally achieved by choosing a small aperture. Depth of field is the front-to-back range of focus in an image, or how much of it appears sharp and clear. The actual size of the aperture will depend on the focal length of the lens.Дeep focus is a photographic and cinematographic technique using a large depth of field. Diagram of decreasing apertures, that is, increasing f-numbers, in one-stop increments each aperture has half the light gathering area of the previous one.

Deepfocus analyst