Occasional doubled images with 40-150

Discussion in 'Native Lenses' started by billy_pilgrim, Apr 29, 2012.

  1. billy_pilgrim

    billy_pilgrim Mu-43 Regular

    39
    Jul 6, 2011
    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!
     
  2. dhazeghi

    dhazeghi Mu-43 Hall of Famer

    Aug 6, 2010
    San Jose, CA
    Dara
    If it's occasional, it's probably not the result of lens damage. What shutter speeds/ISO are you using?

    DH
     
  3. billy_pilgrim

    billy_pilgrim Mu-43 Regular

    39
    Jul 6, 2011
    That is comforting at least! Those shots were at 1/200s, 150mm, f5.6, ISO 250. It was on auto ISO, so that's what the camera chose. I guess that is pushing it a bit for 300mm equivalent.
     
  4. jeffryscott

    jeffryscott Mu-43 Top Veteran

    505
    Jul 2, 2010
    Arizona
    looks like camera movement, not uncommon with longer focal lengths.
     
  5. WJW59

    WJW59 Mu-43 Veteran

    235
    Feb 20, 2011
    What do you have shutter release priority set to? Is IS turned on and set to IS1?

    It looks like either lens movement OR the lens was still focusing when the photo was taken. With IS on, I would expect OK results at 1/200 but I would bump the shutter speed up to around 1/500.
     
  6. dhazeghi

    dhazeghi Mu-43 Hall of Famer

    Aug 6, 2010
    San Jose, CA
    Dara
    As others have suggested, a higher shutter speed would be a good place to start. IS should help, but it's an aid, not a guarantee. The other thing to try is fixing the camera on a tripod or stable surface, and shooting using the self-timer with IS disabled. Testing isn't a lot of fun, but it does help to rule out other variables.

    DH
     
  7. billy_pilgrim

    billy_pilgrim Mu-43 Regular

    39
    Jul 6, 2011
    I had IS on IS1 and release priority S set to off.


    I'm actually having more trouble now reproducing the problem, than I am avoiding it, now that I'm trying to figure it out! I was able to get it to occur at longer focal lengths (> 100mm), with the camera hand-held, at shutter speeds around 100-200, and with IS on. It didn't happen on a tripod, and while I got blurry images without IS, they didn't look like these, with a sort of doubled image. At lower shutter speeds with IS, when it failed, it just looked blurry rather than doubled. So I guess it is probably related to camera movement combined with a failure or perhaps overcompensation of IS. And it still only occurs only some of the time (so I'm not really sure if I nailed down the conditions). I guess I'll just have to watch my shutter speeds, and take more pics and hope some of them turn out well!
     
  8. AnttiV

    AnttiV Mu-43 Regular

    91
    Apr 19, 2012
    Finland
    If that really is an artefact of IS misbehaving or some other weird technical glitch it is a h*ll of a coincidence as it looks EXACTLY like dozens upon dozens of images I've taken with a bit too slow shutter speed compared to zoom. I wouldn't call it a "double image", I'd call it camera shake and be done with it. I've taken hundreds of images that exhibit that exact same "blur/double image" with my Sigma and I've never owned a lens with IS before my G3.

    To my eyes, it is just perfectly normal camera shake that happens if your shutter speed is too slow. Especially with long focal lengths. I have had a rough rule-of-thumb that shutter speed should equal or exceed the focal length times two to (almost) guarantee to shake-free image. So If you're shooting with 300mm (equivalent) focal length, your shutter speed should be 1/600s or faster. There's a bit of leeway here, but generally that has hold true with me.