My 2 cents. I have never seen tilting the lens (front) affect the perspective in any way whether at pictorial (subject to lens distance greater than 10X the focal length) or in macro situations. The back is what adjusts perspective and, of course, does change focus. Standard procedure has been to set the back to get the perspective you want then adjust the front to put into focus those objects on or near the "plane of interest". I believe Jim did mention that this can put you near the edge of the image circle. Also, at pictorial distances there is the 1/3 - 2/3 approximation for depth of field (1/3 of the DOF between the lens and subject plane, 2/3 of the DOF behind the subject plane). However, in the macro region as you increase magnification (reduce the lens to subject dx) proportionally less and less of the DOF is between the subject plane and lens and more and more is behind the subject plane. In macro situations I focus closer to the closest object I want in focus but all of the above is confirmed with a lupe on the ground glass a really DARK dark cloth so that I can still see the image when stopped down. Just my 2 cents. CHEERS! BOB -----Original Message----- From: pure-silver-bounce@xxxxxxxxxxxxx [mailto:pure-silver-bounce@xxxxxxxxxxxxx] On Behalf Of Jim Brick Sent: Thursday, November 29, 2007 2:54 PM To: pure-silver@xxxxxxxxxxxxx Subject: [pure-silver] Re: Large Format Tilt >C.Breukel@xxxxxxx wrote: >>Back focussing is the same as front focussing? I find back tilt to be much better than front tilt for the majority of situations. The reason is that the film stays in the center of the lens's image circle. You can use back tilt with very wide angle lenses and get no cutoff. You cannot use front tilt with wide angle lenses. Therefore, I have gotten accustomed to using back tilt because I have both 55mm & 75mm lenses for my 4x5 and with back tilt, I can tilt 'till the cows come home without ever leaving the image circle. It's a little more cumbersome since the dark cloth and the GG are also on the back standard, but with a little practice, you soon overcome the cumbersomeness. :-) Jim ============================================================================ ================================= To unsubscribe from this list, go to www.freelists.org and logon to your account (the same e-mail address and password you set-up when you subscribed,) and unsubscribe from there. __________ NOD32 2693 (20071129) Information __________ This message was checked by NOD32 antivirus system. http://www.eset.com ============================================================================================================= To unsubscribe from this list, go to www.freelists.org and logon to your account (the same e-mail address and password you set-up when you subscribed,) and unsubscribe from there.