----- Original Message -----
From: "Shel Belinkoff"
Subject: Theory of Equivalency
An 18mm lens on a Pentax DSLR should yield, within a very small degree,
the
identical result as a 28mm on a 35mm film camera. Two pics taken of the
same subject from precisely the same location should be virtually
indistinguishable wrt image size and FOV Is this correct? What, if
anything, should be different between the two pics? I ask this because
something tells me that they will not be the same in some respects.
Depth of field will differ, with the smaller format generating more DOF at
any given aperture.
Not sure by how much exactly, I expect you will probably open up a full stop
to get similar DOF from APS C sized digital as compared to 35mm.
William Robb
