Voigtlander Screw Mount Lenses Heres my view on the new Voigtlander Screw mount lense for the Leica screw mount system. I like the fact that there are focal lengths that Leica does not make.  I would buy these lenses, like the Superwide 12 & 15mm.  The 12mm is a bad performer though, it has horrible vignetting problems.  The screw mount lenses will also work with your M system with a bayonet adapter.  However, the 12, 15 & 25mm lenses lack the ability to focus with the Rangefinder and must be scale focused.  This does not present a problem since these lenses have great depth of field and most would scale focus anyway for this type of photography. Another reason to buy these lenses is to add a lens focal length to your system, M or Screw, because you seldom use that focal length or you simply don't have Leica money.  The 25mm Skopar may be a good choice here if you seldom use a superwide, but would like to have one along on occasion.  Or maybe you use the Screw mount cameras exclusively, like the IIIf or IIIg and would like a 25mm or 75mm lens for your syetm that is not available from Leica in Screw mount. Most of these lenses are very good performers, but they are not Leica quality.  The tonal range and contrast is not quite as good and the build quality is definately not as good.  Lets face it, we like Leica because they strive for excellence above all others, even if it is a small margin at times.  You shoot with the best and you appreciate the time and energy that went into providing you with the very finest in optics.  Your photographs show detail that others do not.  The tonal sepration is beyond reproach and adds a quality to your photographs that others lack.  So why put Voigtlander lenses on your Leica when you can have Leica lenses!  The 35mm Asph & 50mm Summicron is now again available in screw mount so get them while you can. Buy the Leica lenses when you have a choice and the Voigtlander lenses when you do not.