First off, hello everyone. I've been looking for a good Photography forum for a while now. I'm just getting into photography and I'm getting my second DSLR. I really like the concept of reverse mounting your lens for macro work, however, I don't really want to be exposing the rear end of my $1500 lens to do it. So I'm looking for just an old lens that has a 58mm or 52mm filter ring that I can use for this purpose. Obviously autofocus doesn't matter and a manual aperture ring would be ideal. I'm using this on a 7D but I'm thinking that an old, prime, wide angle, manual lens would be my best shot. I won't be using the lens a ton so if I could find one on eBay for around $10-$20 that'd be fantastic. I don't care about brand. All of my stuff is Canon but I'll definitely make an exception for this. So to sum that up, I'm looking for a lens that is: -Wide angle (below 30mm) -Preferably prime -Full manual (focus, aperture) -58mm or 52mm filter ring -above all, Cheap. Thanks for any help!