Archived posting to the Leica Users Group, 1998/10/22
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Kevin, to answer your question, the bayonet adaptors are of the exact thickness to compensate for the differing flange-to-film-plane distances between screw-mount and M Leicas. If the lens acts the same on both of your M's, it is possible that the focus mount (which on older Leica lenses at least, was adjustable) is "off" and the lens is out of collimation. That could be adjusted by a competent Leica-trained lens repair person. My recommendation is Jon VanStelten of Focal Point in Colorado, USA. You might also want to consider that the Summicron in screw-mount was a very low-production lens. If it is the type with a removable rather than integral lens hood, it is rarer still. If your lens is in fine condition and you don't have a sentimental attachment to it, you might be able to recover sufficient funds from its sale to afford a new(er) lens. Or do as I have done and "semi-retire" my older lenses (a euphemism for my being a sentimental old sot and unable to part with them). Regards, Nigel On Thu, 22 Oct 1998 09:44:34 -0700 "Khoffberg" <khoffberg@email.msn.com> writes: >I'm new to LUG and have enjoyed reading your various missives. Here's >my >question. > >I have an older screw mount Sumicron 90 which I inherited from my >grandfather. I use it on my M3 and M6 with an adapter ring. I've >noticed >that when you try to focus at infinity that the images don't quite >line up >in the range finder - you can't get them all the way there even though >the >hyperfocal scale says infinity. Any thoughts? Is it possible that the >extra >thickness of the adapter ring is causing the problem? If so, wouldn't >the >same problem hold true at all other distances? > >My test slides under a 10x loupe look sharp at various distances but >I'm not >sure if that's just a function of being stopped down and depth of >field (the >test I just did was at f16. It didn't occur to me to try other f >stops). > >Thanks in advance. > >Kevin Hoffberg >(925) 942-2772 >Visit our website at www.inseon.com > > > ___________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com/getjuno.html or call Juno at (800) 654-JUNO [654-5866]