Yes it will also depend on the printing magnification Chris http://www.chrisssoftwareshop.co.uk/ http://www.chrisscrazyideas.co.uk/ http://www.chrissimageshop.co.uk/ -----Original Message----- From: owner-photoforum@listserver.isc.rit.edu [mailto:owner-photoforum@listserver.isc.rit.edu]On Behalf Of PhotoRoy6@aol.com Sent: 09 September 2002 04:56 To: List for Photo/Imaging Educators - Professionals - Students Subject: Re: Two basic and dumb questions about lenses 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)
