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The rare SLII version of the Voigtlander 90mm on Ebay for a good price.
I've owned both the SLI and SLII version of this lens, and I've also owned the Voigtlander 125 and 180, of which there are only SLI versions. A lot of people gush over the 125 and 180, but don't realize the 90mm is almost identical in terms of IQ. The 125 is of course a dedicated macro, so gets close up and has ultra-sharpness across a flat field, but the 180 and the 90mm are ridiculously sharp too, and the 90mm gets very close as well. Besides super sharpness they all shared rich color rendering, contrast and micro contrast . . . with no differences that I could discern.
I sold all my SLI version Voigtlanders because of their stiff focusing rings. For manual focus, especially telephotos, I personally need the focus ring to glide. So when I discovered the SL II version of the 90 has very smooth and easy focusing, it became a permanent member of my small lens kit. It also comes with a little close up lens for those of us who don't need a dedicated macro lens. Other cool things about the 90 SLII is how lightweight and small it is, and the screw-on hood that allows for attaching the close up lens can be left on full time as a lens hood. All in all it is one of the finest lenses I've ever used.