The big problem is finding a reputable site to look this up. Internet searches bring up so many conflicting answers, even from the so-called authoritative sites, that optical physics seems based more on opinion and limited experience than optical laws. So I wasn't questioning the validity of your answer; I was trying to see how my observations could be accounted for by the answer. This topic has come up on PDML several times before, and there are always at least two people, with two conflicting answers, who both insist that they are right.
I'll hit the books sometime later and see what actual published works have to say about it, as I suspected edited materials will tend to be more accurate than most websites. So, just to clarify, if I take two photos--one with a 28mm lens and one with a 100mm lens--while standing in the same spot and shooting at the same aperture, and then enlarge a segment of the 28mm photo until it has the same coverage as the 100mm shot, the perspective will remain the same, but the DOF will be different? That's what I'm trying to understand... I thought that the DOF would be the same as well. Thanks, chris On Wed, 24 Sep 2003, Bruce Rubenstein wrote: > You make it sound like some sort of optical physics that I made up and have > to defend. I just try to keep track of what does what. Beyond that I would > suggest some independent research on the topic. Not to be snide, but I see > endless discussions and arguments over things here that can be looked up. > > BR > > From: Chris Brogden <[EMAIL PROTECTED]> > How do you account for the fact that p&s digital cameras can still blur > the background for some portrait shots? With focal lengths around 7-12mm > or so, pretty much everything should be in focus, shouldn't it?
