To adapt #practikar B mount to my #Canon #6D I actually just removed the old flange, did some calculations and 3D printed an adapter. It was a 1hr print on the #SLA #Mars3. I used their water based #resin, but next time I'm going to use my newest resin #resione #W90d. So far that's the best resin I've tried. They got a black version of it.