I just purchased this lens and have been shooting with it for a few days. Posted a few pics in the POTD thread. The major interesting thing about this lens is it's huge maximum aperture--f/0.95. The only other 50mm lens with this wide of an aperture is the Leica Noctilux--which is over 10x more expensive at ~$11k USD. I didn't have high hopes for the Mitakon, but couldn't resist. In general I've been pleasantly surprised. Don't get me wrong, it's not a Noctilux. But it performs well, is actually affordable, and is more usable (on a Sony it can be easily focused with the standard EVF, for the Leica you would really need a body that can use an external EVF as DOF at f/0.95 is relatively shallow and standard rangefinder focus would be very hit-or-miss). Took an exposure series to share. Rather than post all the images here (and eat up bandwidth) I'm posting a link to an LR gallery. The subject was just under 4 feet away. Constant mixed indoor and outdoor light between shots and all taken on a tripod. I kept ISO constant at 320 for the series. These are the RAW files without any changes at all in LR. This series starts at f/0.95 and goes to f/16 in (mostly) full stops. So the first is at f/0.95 (1/320 sec), the second at f/1.4 (1/200 sec), the third at f/2 (1/125 sec), the fourth at f/2.8 (1/60 sec), the fifth at f/4 (1/30 sec), the sixth at f/5.6 (1/15 sec), the seventh at f/8 (1/8 sec), and the last at f/16 (0.6 sec). I skipped f/11 because the lens doesn’t have an aperture mark for f/11 and the aperture ring is continuous without clicks for stops—slightly annoying for a shooting series like this. https://adobe.ly/2sRKXhV The histograms would be interesting to share so you could see if the exposures were roughly equal for each exposure combination. Not sure how to share that via the LR collection or how to even share exposure/exif info in an LR web gallery (would be happy to learn how to do this if anyone knows--thought I had checked all the appropriate buttons in the web module). In general, the histograms were similar between shots. There is significant vignetting at f/0.95 compared to the other apertures (which is expected). The sharpness is actually pretty close in this series—better stopped down to f/1.4 compared to f/0.95, but only really evident when pixel peeping. I have other shots where there is a clear difference between f/0.95 and f/1.4--a little softer at f/0.95. But if you really need f/0.95 (for either low light or subject isolation) the sharpness difference may not matter. Since there aren't really any other viable alternatives, it is what it is. There is a difference in DOF with 0.95 compared to 1.4 but it isn’t crazy (though it's still obvious). The exposure difference between 0.95 and 1.4 is there, but not sure it’s a full stop (guessing it’s closer to between 1/2 and 3/4 stop comparing the histograms, but the vignetting difference between the apertures makes it hard to be sure). Lens construction is solid. It's dense. The aperture ring is smooth, but as mentioned above doesn't have clicks. The focus ring moves smoothly and it has a nice focus throw--reminds me of Zeiss lenses. Anyhow, thought there might be some interest in this lens. Only available (I think) for Sony e-mount.