DOF2

 
Testing The Theory
Most photographers accept the common belief that short focal length lenses have greater depth of field than do long lenses. A wide angle lens, in other words, will give greater depth of field than will a telephoto. Right? 
Sounds about right, but it's not the case.In fact, if the subject image size remains the same, then at any given aperture all lenses will give the same depth of field.
Because this is such a controversial statement, and because it initially flies in the face of common experience, I have created the following set of example images. 
The set-up for it was as you see below. Camera on a tripod and two light stands holding test subjects‚ a gremlin, which is the main subject, and a hand puppet the other. A tall tower at infinity is the third.

Each of the frames below was taken so thatthe gremlin doll is exactly the same size in each frame. I used the camera's circular center focusing spot as a size reference. The gremlin doll just fil...