on Nikon is hard to use it (adapter does not allow infinite focus), now on Sony i think you could. most common is m42 mount. Most popular for modifications are 44-2 and 44-4 (bigger the number newer lens). They made a lot of them so you can find one for 20-30$
Helios overall is interesting, but it is manual focus lens. There is 85mm f/1.5 that is also quite popular. in the right conditions you get this swirly bokeh. It looks interesting.
on Nikon is hard to use it (adapter does not allow infinite focus), now on Sony i think you could. most common is m42 mount. Most popular for modifications are 44-2 and 44-4 (bigger the number newer lens). They made a lot of them so you can find one for 20-30$
Helios overall is interesting, but it is manual focus lens. There is 85mm f/1.5 that is also quite popular. in the right conditions you get this swirly bokeh. It looks interesting.
Need to borrow that lens to do some portraits.