Sir, MY "burden of proof" is no greater than yours. If you cant provide any reliable "proof" that my contention is not true, then your word is no better than mine. I dont need any more "proof" to support my contention than you need to support yours.
This is very simple. DOF is all about magnfication and f-stop. I did supply the formula, relative DOF = F-stop number/MAGNIFICATION. INCREASING F-STOP NUMBER OR DECREASING IMAGE MAGINIFICATION increases the image relative DOF. Conversely, DECREASING THE F-STOP NUMBER OR INCREASING THE MAGNIFICATION decreases the image relative DOF. If you dont believe me, do some experiments. I have, its called about 35 years of practical experience to back up what I have read in theory. This isn't my theory, this is the correct theory that I have read and found to be true over the years. JC O'Connell hifis...@gate.net -----Original Message----- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Bob W Sent: Tuesday, April 07, 2009 3:00 PM To: 'Pentax-Discuss Mail List' Subject: RE: Trading resolution for depth of field > > The entire thread and original post was all about > > the relative DOF ( how to increase or decrease > > DOF in an image relative to ANY reference DOF ). > > But your claims regarding relative DOF are only valid if the image > format (film size, crop factor, whatever you want to call it) is > constant. > > A change in format leads to a change in allowable CoC, which you're > dropping on the floor. If you dispute that the allowable CoC is > different for different formats, then you are the one who is claiming > there's an "absolute" DOF. > > =========================================== > > NO NO NO NO, > > My post is ALL INCLUSIVE. The only thing that affects (increases or > decreases) > the image DOF is : (the image magnification in-camera) & > (f-stop used). > Format, crop > factors, COC, print size, etc, blah blah blah have ZERO effect on DOF. > That is the common myth > I am trying to dispell. Its all about image magnification and > f-stop and > THATS IT. > Changing the format, film size, "COC" means nothing..........ONLY > changes to the image magnification > and f-stop change the DOF. > You seem very certain about this, but you won't provide us with any objective criteria, such as a formula, by which the people who disagree with you can come to any conclusion. Why not? Why don't you provide us with some evidence, then we'll shut up about it? Give us a depth of field formula in which all the terms are constant, except for image magnification in camera and f-stop, and in which viewing distance and coc have ZERO effect. Go on, be a sport. Bob -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
