I love this thing. I use it on a mirrorless Sony with an adapter. If you're not used to focusing manually, you'll have a lot to learn with this f/1.25 lens as the depth of field is very shallow. But it's sharp wide open, the minimum focus distance is as close as you want it and you can get crazy separation at long ranges. It's very heavy, but I still carry it with me because I love shooting with it. It's also incredibly well made. It's all metal, the focus ring is smooth and well-damped, and looks expensive. I used to have a vintage Leica 90mm Summicron from 1969 (I loved that lens but it was stolen). The results I get with this lens are better than Leica (yes I said it come to me).
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