One reason why the Voigtlander 15mm is popular is because of its Lightweight
Reviewed by 4 customers
Wonderful little jewel of a lens works like a dream on my M8.2
I bought this lens before the GXR A12 M module was released, so I wasn't able to try it out until I received my M module. The lens is well made, has smooth manual focusing, is very sharp, and is optically well-corrected. With an APS-C sensor it is the equivalent of 22.5mm which makes it a very useful wide angle lens to have. It's small size, top quality construction, and ability to take 52mm filters are big pluses. And, although not cheap, compared to Leica lenses the Voigtlander is a bargain.
The lens causes a red shift on the corners when used with the M9. It can be fixed via software though. The lens is super sharp at 4.5 and it is rangefinder coupled. So you can get great focus even at subjects that aren't far away. There is also minimal to no distortion. The lens is a bargain compared to the Zeiss and Leica ultra wides. It's also so much more compact and lighter than the Zeiss and Leica counterparts. However, pricewise, compared to other Voigtlander ultra and super wide lenses, it's not such a bargain, especially because it doesn't come with a viewfinder (which is at least another $140). I ended up returning this and getting an used Voigtlander Skopar 21/4 for $280, including a viewfinder.
I bought this at the Adorama store while visiting New York, and that's where I could immediately put it to use, to get all those landmark buildings in one frame without having to walk back 10 street blocks. I see myself using this for cityscapes and to a lesser extent landscapes. Great: even though it is rangefinder coupled, you really don't need it. At f/4.5 it's already possible to get DOF from 1m/3ft to infinity. At f/8, you really don't need to worry about focussing. The downside of that is that selective focus is not really possible. Great/not so great: Depends on what you want/expect. At f/4.5, there is some vignetting. Personally, I like it; it goes away at f/8 or above, so if you don't want it, just close the diaphragm. Not so great: wide open is f/4.5. At ISO100 on a rainy day or indoors, you are stuck with times of 1/15s or longer. Again, I knew what I was buying, so I don't mind. But it's something to be aware of. As background information: I use this lens with a Voigtlaender Bessa R3M film camera (in other words: "full frame"). At time of writing, I have only shot colour negative film using this lens. I'm curious to see the results with B&W film.