Every once in a while (actually far too often) the bug hits me to try something new with new gear. I've been using my NEX almost exclusively with my 28mm Ultron since I got it and now I'm wanting to try something wider in a rangefinder lens. I'm thinking of selling my Contax lenses (not an easy decision) to fund the purchase so my budget is limited. If my budget wasn't limited I would probably get the Zeiss ZM 18m f4 as it would give me a roughly 28mm equivalent lens and that seems ideal to me, but at $1300+ it is out of my price range. So my choices are down to two Voigtlander lenses: the 21mm f4 and the 15mm f4.5. The 21mm really appeals to me for its small size and good optical quality, but I'm afraid it is too close to my 28mm to be a really adequate wide-angle solution. A 32mm equivalent lens really doesn't seem that wide. On the other hand the 15mm is an equivalent 22mm lens and maybe a touch too wide for me although the 21mm focal length in the right hands can be a stellar focal length for street and documentary photography. And of course, I can always crop the 15mm focal length to make it less wide. Perhaps in writing this the choice seems a bit clearer for me but I'm curious to hear the advice of others before I take the plunge.