In
optics, particularly as it relates to film and photography,
depth of field (
DOF), also called
focus range or
effective focus range, is the distance between the nearest and farthest objects in a scene that appear acceptably sharp in an image. Although a
lens can precisely
focus at only one distance at a time, the decrease in sharpness is gradual on each side of the focused distance, so that within the DOF, the unsharpness is imperceptible under normal viewing conditions.