What is Depth Of Field?
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.
What is deep Depth Of field?
So an aperture of f/2.8 is wide, while an aperture of f/22 is small. Again, focusing distance plays a part on the overall effect, with wide apertures offering considerably more depth of field when focused on a subject far away than they do when focused on a subject that's close to the lens.