Where can I find specs for R lenses?

<p>I'm not familiar to the Leica R system, but have begun playing with the idea of buying an R Leica lens to adapt to my Nikon just to try the mechanics and optics of Leica lenses. However, I noticed that the Leica site seems to list only current lenses and I would like to compare specs for older lenses also (I'm a bit interested in the 180/3,4 APO). Is there some site that would list the specs of Leica R lenses, past and present? By specs I mostly mean things such as physical dimensions, filter size, appearance of the lens and if possible serial numbers. MTF graphs would be nice too, but I don't expect them to be that easy to find.<br>

A bit related to this is how to tell different editions of the lenses apart? It would be easiest if the serial numbers are available for all models, but as a newcomer to the Leica system I find it a bit difficult to be sure in a web auction which version of a particular lens is being sold.<br>

Any help is appreciated.</p>

<p>MTF graphs for some of the previous generation R lenses are at: http://old.photodo.com/nav/prodindex.html</p>

<p>Click on "mtf tested only" and "35mm and APS" and then scroll down to the Leica R section. Sometimes they list physical specs and have an image - sometimes not. But they will all have mtf charts. I found it really useful when first getting into the Leica and Contax rangefinder lines. I believe the photo.do tests were done by a Hasselblad employee on Hasselblad's in-house test bench in the 90s sometime.</p>

<p>Doug Herr at http://wildlightphoto.com had an info database on R lenses at one point - but it is private due to people swiping his images for *bay auctions. You may be able to get permission to view it from Doug.</p>

<p>Erwin Puts's Leica Lens Compendium has information on the R lenses. You should be able to find it somewhere online. I am not sure if it is still up at his site. </p>