Archived posting to the Leica Users Group, 2003/07/24
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]I tried posting this on the list a couple of days ago, but it wouldn't stick. Here's another attempt .... It might have been a problem with italics. Hi Ted, sorry for my slow response to your reply on this. I used to think the rangefinders I had might have been off, but the results were too consistent between bodies, across a variety of lenses and experienced by other photographers to leave it at that. So I did a little layman's research. Upon testing the lenses for focussing accuracy, the bodies and lenses come up fine. I did notice however that the bulk of the zone that is acceptably in focus is behind the point of focus. No surprise here - the 1/3 in front to 2/3 behind rule applies. And herein lies the difference between using a rangefinder camera and using an SLR with a ground glass screen. When I use an R camera with ground glass, I twist the lens to bring the focal plane slightly in front of the subject and then move it back until the subject's eye is just in focus. This tends to leave the focal point slightly ahead of the eye, as I have put the middle of the in-focus zone on the eye. But with a rangefinder, the practice is to superimpose the patch images, which means that 1/3 of the zone or depth will be in front of that point (or eye) and 2/3 behind. So if I want to get a result with a properly calibrated rangefinder that resembles what I would get with an SLR, I would need to tweak the rangefinder's lens ever so slightly clockwise after focussing properly, to bring the focal point closer. Drawing it out on paper makes it easy to see how one gets different results with SLR vs rangefinder and how this approach works. Once I'd figured it out, practicing it simply proved it. I get far fewer shots with the zone of best focus on the subject's temple or ear rather than on the eye these days. Works for me. Regards, Rick Dykstra, Australia. - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html