A little while ago I got a reversing ring as a cheap macro option now that spring is in full swing here. Originally I had thought to use it with my Canon FD 50mm 1.4 but I quickly realised that I don't get much magnification with that lens on m43. My kit zooms look like they'll work ok and my panny 20mm gets me plenty macro (albeit I have to be on top of my subject) but I'm not sure how to set the aperture. I saw one blog where the photographer suggested taking a long exposure photo with the desired aperture and then taking the lens off mid-photo but that sounds like an awful idea to me. Any better ways to achieve this?