Aye aye fellow legacy glass addicts. My Pentax PK adapter got here this morning (Fotga brand, cheapo and very nice). It allowed me to try the superfast Porst Color Reflex Auto MC 55/1.2 that I had received a few days ago from Germany. The lens receives mixed reviews on specialized sites like MFlenses.com and such. People seem to love it or hate it, and wild theories go about who designed it (Tomioka ?) who built it (Cosina), etc. My copy's serial number starts with zero, so unless I'm mistaken it's an early one. Few superfast lenses are very sharp wide open (none ?). Some are sharper. This one is definitely soft at 1.2, so let's move on to F2, or slightly before that, since there is no intermediary stop written on the aperture ring, but it is physically possible to set the ring somewhere between 1.2 and 2, that's what I did for this test. The whole purpose of SuperFasts is to throw backgrounds out of focus in an elegant and pleasurable way. I think the Porst does that very well. Someone wrote in one of the board discussions I read while I was researching it prior to buying, that it's a difficult lens to shoot. I totally concur. Even with my daily practice of wide open (or very close buy) sharp prime shooting, DOF is so incredibly razor thin on this lens you're in for a lot of not critically focused shot if you're trying to nail a 4 yr old. OTOH, I'm sure a studio fashion shooter stopping it down to 4 would be all over this lens. It has some very nice qualities. It's a well built, classy looking and exotic by its rarity piece of glass. It handles very nicely. It's very compact for a SuperFast. It renders lovely mushy melted backgrounds with blissful light rounds in almost perfect circles. The above shots have been tinkered with a bit in PS. Slight boost in contrast, and selective sharpness. If one doesn't mind spending just a little time in front of the computer, that's a very fine lens. I think it is particularly well suited for portraits, weddings, newborns, and fashion. So personally I neither love nor hate it, I recognize its use, and despite its softness at wide apertures, I feel drawn to it and want to use it. Any comment or further questions welcome !