These are screw/threaded type if I understand correctly. Are all Leica screw/threaded lens the same thread size? I see a lot of them on Ebay.going on holidays soon would appreciate some advice on some wide angle m42 lens some beach photography any one got any ideas which are quite good for this please help
Dan -- M42 are old SLR lenses & have a 42mm diameter thread mount ; the old Leica thread (variously also known as Leica screw mount/LTM/L39/M39) mount is 39mm.
I'm not quite sure what bryanashford is asking here?