In a message dated 9/8/02 1:45:24 PM EST, Bob@Blakely.com writes: > ow, you may be tempted to say that this is only apparent because the 100mm > photo must be blown up by a factor of three to provide the same cropped > scene. Consider that 0.285 x 3 = .755, not 2.659. My Physics Professor in college actually did this with actual photographs and concluded that the DOF was the same as long as picture is shot from the same spot at the same f/ and the pictures are enlarged to same magnification.(i.e. 100mm blow up 3x of 300mm)
