Archived posting to the Leica Users Group, 2005/03/10
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 08:03 AM 3/9/05 -0500, Lew Schwartz wrote: > I believe that there was a reference in this ng to someone who can >modify Soviet LTM's to focus properly on Leica and Cosina screw mount >bodies. Has anyone any experience with this repair or recall who does it? Lew With very few exceptions, all Postwar SPS (Soviet/Post-Soviet) LTM lenses focus accurately on Leica bodies. The few exceptions are caused by improper manufacture and poor quality control. Lenses properly constructed work without a problem; conversely, Leitz and Leica LTM cameras will jazz up your Zorki or Fed body a bit without a problem. Prewar FED lenses generally have problems, both in terms of quality control and in terms of construction: as was the case with early Japanese LTM lenses, the manufacturers imagined that the LTM's dimensions were 39mm by 1mm, while it is actually 39mm by 26 turns per inch, Whitworth thread (remember that Leitz made microscopes, and microscopes a century back were generally produced in Whitworth threads, though the RMS mount actually predates Whitworth); this works out to 39mm by 0.977mm, and, for those of us old enough to remember the reference, that "silly 0.23mm" made all the difference, causing many Prewar FED and early Postwar Canon lenses to bollux up when attempting to mount them on a true LTM body. (I will admit that I have owned and used a number of Prewar FED lenses and have never encountered a problem with them on LTM bodies, nor have I ever encountered a problem with Postwar SPS lenses.) Marc msmall@aya.yale.edu Cha robh b?s fir gun ghr?s fir!