Sorry, my mistake. Pentax writes that a lens used on APS-C has narrower DOF
than the same lens used on 35mm, not narrower DOF than an equivalent lens
(e.g. 50 vs 75mm). So please disregard my conclusion, I have to re-think
them. However, now I have to leave. Maybe tomorrow...
Kostas, didn't you notice? From time to time I've already been back here for
some time (even if not as active as I was years ago). However, thanks for
your "welcome back".
Bye,
Dario
----- Original Message -----
From: "Kostas Kavoussanakis" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, July 14, 2005 4:26 PM
Subject: Re: Theory of Equivalency (slightly revised)
On Thu, 14 Jul 2005, Dario Bonazza wrote:
2) Circle of confusion (COC=a lens design parameter, different for
different
<snip>
For this reason, a 50mm lens used on APS format should show less DOF than
a
75mm on 35mm format (provided that both lenses are designed for 35mm and
are
set on the same relative aperture).
Should that be "on the same absolute aperture"?
Many thanks for taking the time to write this. It's nice to have you
(back) on the list.
Kostas
