depth of field is determined solely by in camera magnification and working fstop. So cropping/format is not a factor but changing lenses from a given distance will affect DOF, likewise moving further away with the same lens and stopping down more will also both increase DOF.
JC O'Connell [email protected] -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Larry Colen Sent: Monday, April 06, 2009 4:35 PM To: Pentax-Discuss Mail List Subject: Trading resolution for depth of field Perhaps someone has already done the math, or the experimentation, and can just give me the answers. Scott's pictures of his Nishiki inspired me to shoot some of my mongrel legnano. I rode it to lunch today, and on the way back to the office was getting some shots of it with some lupin by the side of the trail. I didn't have quite as much depth of field as I'd like, so I decided to try zooming way out and then just cropping. Smaller sensor, shorter lens, more depth of field. If the equation is linear, I should get the same DOF by downresing (downrezzing?) a longer lens over the whole sensor, as I would using a shorter lens and cropping. This would also mean that a K20 would have a lot less DOF than my K100 at the same focal length, assuming that they were blown up large enough that the sensor resolution became a factor. So, if I'm willing to trade resolution for depth of field, am I better off using a wider angle lens and cropping (my intuition says yes), or do I get the same benefit by just combining pixels (which would also reduce noise) for a larger circle of confusion? -- The fastest way to get your question answered on the net is to post the wrong answer. Larry Colen [email protected] http://www.red4est.com/lrc -- PDML Pentax-Discuss Mail List [email protected] 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 [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
