I asked this two+ years ago without much helpful response. Decided to pursue the topic again. When I got my GH2 in 2011, my dad gave me his old Canon lenses. Most weren't anything special, but there's something about this one that just feels NICE. Perfect shape, other than the aperture blades are stuck. Googling said it's a pretty common problem, oil build up, but I can't seen to find a way to take it apart. Everything else looks good on it, no fungus that I can tell. I have a connect for lens repairs, I'm guessing it would be around $45? Is there any history with this lens? On ebay they've gone for $19-$200 in various mounts. I don't particularly need the lens, but since it has some family history I'd quite like to use it (perfectly smooth focus ring too), but don't want to invest the money if these aren't any good. Thanks for the thoughts.