I didn't see a thread on this lens so I figured I'd start one. I wanted to do a little test between wide open and stopped down a bit. In terms of contrast and sharpness, I'd say ƒ4 is ideal. At ƒ2, contrast is low and it's a bit soft. Both shots were taken on an Olympus E-PM2 on a tripod. No post processing... actually, I did remove the CAs from the ƒ2 shot in Lightroom. Wide open, this lens tends to show a bit of purple fringing (most of the older lenses I've used tend to exhibit this "feature"). Here's the ƒ2 shot. CAs were mostly in the highlight in the reflection in the eye. As you can see, it's slightly soft in the center due to low contrast. Nothing you certainly couldn't fix in post. At some point, I'll post some better bokeh examples. Olympus OM 35/2 @ ƒ2 by mr.sesser, on Flickr Here's the ƒ4 shot. It's definitely sharper and more contrasty at this point. Olympus OM 35/2 @ ƒ4 by mr.sesser, on Flickr Here's a couple 100% crops: @ƒ2 @ƒ4 Stay tuned for more samples. I know I have some older ones taken with my old GF1 I just sold.