Some months ago, I purchased a Canon FD 50mm f/3.5 Macro lens from the ShopGoodwill.com auction site. It was part of a package, which also contained an old FD telephoto lens and a set of three macro adapters in a nice case.
Everything that I'd read about this lens indicated that you got a lot of bang for your buck with it. This is a typical blurb that you see for it on auction sites:
"Optically excellent Canon Macro lens. This lens is believed by many enthusiasts to be among the sharpest macro lenses ever made for the Canon camera."
Here are a couple of shots that I took last evening:
The hardest thing with this lens is having to manually focus. As you can see above, however, it can be done.
I'm keeping the 1x macro adapter on this lens to protect it and keep it clean, so these two shots aren't simply with the "pure" lens. It's weird as far as lenses I've had. The front has a deeply recessed cavity, so protecting the lens itself really shouldn't be an issue.
I've been thinking of selling this lens and the adapters on eBay, but I think that I want to play with it for a while longer.