The distance between the nearest and the furthest objects giving a focused image. the zone of acceptable sharpness within a photo that will appear in focus. In every picture there is a certain area of your image in front of, and behind the subject that will appear in focus. This zone will vary from photo to photo. some images may be very small zones of focus which gives it a low depth of field. Other photos may have a larger focus which is called a deep depth of field. Three main factors that will affect how you control the depth of field of your images are aperture, distance from the subject to the camera and focal length of the lens on your camera.