Fences, Windows, and Autofocusing

Discussion in 'Open Discussion' started by hunyuan7, Jan 3, 2012.

  1. hunyuan7

    hunyuan7 Mu-43 Regular

    Aug 31, 2011
    How do you get your camera to focus on a subject that is behind a fence and window?

    My G3 keeps autofocusing on the fence and window and not the subject behind them. What solution do you have in these situations?
  2. FastCorner

    FastCorner Mu-43 Veteran

    May 28, 2011
    Decrease the focus box size and aim past the fence, or switch to manual focus.
  3. supermaxv

    supermaxv Mu-43 Veteran

    Sep 20, 2011
    Manual focus.
  4. Aegon

    Aegon Mu-43 Veteran

    Nov 3, 2011
    Portland, OR
    Ask her out for dinner and you can use a regular portrait lens instead of a telephoto lens through the fence.
    • Like Like x 3
  5. Promit

    Promit Mu-43 All-Pro

    Jun 6, 2011
    Baltimore, MD
    Real Name:
    Promit Roy
    So here's a neat trick: you can assist the autofocus with manual control. This might require S-AF/MF mode, I don't remember. In any case, you need the focus ring to actively control focus. Now all you have to do is zone focus as close to the target and as far from the obstruction as possible. Shooting through a window, for example, the window is usually quite close and the subject quite far, so throw the focus out to the far end. THEN trigger the autofocus.

    AF searches for a high contrast area close to the current focus setting. By manually pulling focus away from an obstruction, AF will find a whole new range of targets (hopefully) and won't be so interested in the window. I do this all the time from cars.
  6. hunyuan7

    hunyuan7 Mu-43 Regular

    Aug 31, 2011
    @fastcorner: What is the focus box? How do you decrease it? Gosh, I feel like a Luddite for asking. :)

    @promit: Thanks. I will try.

    @aegon: I wish that were the situation, but I was photographing exotic African birds at the zoo. These birds were in their fenced in dome environment.

    @everyone: I tried manual focusing, but with 100-300mm lens, the focusing feel was awkward and hard to manage. I just prefer sticking with autofocusing with the 100-300mm lens.
  7. FastCorner

    FastCorner Mu-43 Veteran

    May 28, 2011
    Not sure how it works on the G3, but on the G2, you can use the thumb wheel during manual focus point selection to change the focus box size.
  8. meachp

    meachp Mu-43 Regular

    Nov 16, 2011
    Norton-on-Tees, UK
    Press left arrow (brings up AF mode)

    Press down arrow.

    Now you can use the thumbwheel to resize the focus box, and the arrow keys to move it around the screen.

    Hope this helps.