I was using interchangeable lens rangefinder camera's when I discovered the Soviet lenses on the internet in 1999. I bought a black 1984 Jupiter 9 in Contax RF mount, in '99, from a seller in China. I sent him $75 of US currency, in cash, and a few weeks later received the lens. It turned out to be one of my favourite lenses ever. I also purchased my first slr in 1999, an Olympus Pen F (half frame.) At the time I didn't know anything about lens registrations, but holding the lens, set to infinity focus, in front of that Pen F body, I saw that it was possible to make an adapter to couple the two together and I did so. The infinity focus, at f2 aperture opening, was calibrated to exactly .75 mile, because that's how far away the radio tower was that I used to calibrate with. Unfortunately the effective resolution of the lens, which wasn't so stellar even on 35mm/24mmx36mm/full frame, was greatly diminished with the half frame format. I soon lost interest in the Pen F and picked up a Nikon FTn and soon after sold all of my gear to concentrate on learning everything that I could with the Nikon slr gear. Sometime in 2001 I realized that photography had really lost it's thrill and after evaluating I purchased some more rangefinder cameras, this time in Leica screw mount. This is when I purchased my first Jupiter 3 lens.