I've menaged to get this m42 enlarger lens for cheap. It doesn't have built in way to focus, and when mounted in slr it's focused beyond infinity. I want to know if, and how, it can be used with analog slr. I already tried macro bellow, but that setup couldn't focus on infinity.
I’ve not tried using enlarger lenses before so I don’t think I can help too much but you can get those helicoil adapters.
I assume the macro bellows is just too far from the film plane to provide infinity focus.