Ooo, what an exotic looking setup!
Leitz Elmarit-M 135mm f/2.8 from about 1984 mounted on a 1958 Leica M2 with MR-4 Leica-Meter.
It would seem that despite being a fairly popular and relatively affordable lens, there's not a whole lot of good information out there on the internet about it. There's a lot of people that say it's way too large and that the slower aperture Leitz lenses are a lot better (which I don't doubt), but that's about all I ever seem to see anyone say about it.
The longer the lens, the more difficult it is to focus on a rangefinder. Since we're dealing with a lens here that's both relatively fast aperture and fairly long, Leitz compensated for some of the increased difficulty in focusing by building in a set of magnifying goggles. These goggles turn the 90mm brightline into a 135mm view by giving the viewfinder an extra 1.4x magnification and effectively enhances the accuracy of the rangefinder. It does darken the viewfinder image a little and I think it also increases the tendency of the rangefinder spot to flare out, but all in all, it's a intriguing solution.
The lens is obviously kind of large, but not really any more so than any other 135mm lens like this would be. This particular version of the lens was the last version (sometimes denoted by the option for E55 filters as opposed to the earlier Series 7?) and was optically the same as the R-series lens that Leitz made for the now discontinued R-system of SLRs. There's definitely some heft to it; I'd say that with it mounted to the M2 the whole kit is maybe five pounds, so yeah, it's not exactly lightweight, but what do you really expect from such a solidly built package?
The person I bought this lens from said that he used it on an Epson RD-1, but I don't see how that's possible as the goggles don't line up with the rangefinder windows, and I can say for certain that the lens does not work with the Voigtlander Bessa series of rangefinders. It might work with the Konica Hexar RF, but I've never played with one to know what the differences are, and my guess is that it won't work with the new Zeiss Ikon M-mount rangefinder either. It does, however, work fine on the newer digital-Ms, but on the M8 (at least on an unmodified M8 anyway) the frame lines aren't 100% accurate, but they are usable.
Functionality aside, the lens is quite sharp, no surprise there, but what did surprise me is how prone it is to flare. Any sufficiently bright light source can lead to a dramatic veiling flare that doesn't necessarily ruin a photo, but does reduce contrast significantly. I suppose this might be highly desirable in a portrait lens, and certainly 135mm makes for a great portrait focal length, but this still surprised me a bit. As I said, the lens is very sharp (not uncommon for a 135mm) and doesn't really need to be stopped down to improve. If you've got one of these lenses and you think it's not quite up to snuff, you might want to calibrate it--sharpness really depends on critical focus. Fortunately you can do this yourself by loosening (but not removing) the back of the goggles and adjusting the set screws near the goggles' objectives.
All in all, a very nice lens.
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