I have a native Oly 40-150 and I'm generally very happy with the results. Recently I discovered that at the short end it makes a very nice portrait lens! However, sometimes the images I get with it have a sort of doubled image effect which you can see at high-contrast edges, making the image much less sharp than it should be. This only seems to happen at longer focal lengths, and never at 40mm. Here are a couple shots from yesterday, taken seconds apart at the same settings, with the first displaying this problem and the second not. Unfortunately the first is the better moment! Photo Album - Imgur So I want to know why this is happening. Is this due to handshake, or an artifact of the IS system (I use an E-PL2), or is there something wrong with the lens? I did drop it once from a couple feet on to a sidewalk. It had a plastic hood on that absorbed a lot of the impact, and the focus and aperture motors still work fine. I haven't noticed this happening with any of my other lenses, but this is the only long telephoto I have that I really use. Any advice? Is this likely a result of lens damage, or is there some way I can avoid this problem? Thanks!