Panasonic 20mm issue?

Discussion in 'Native Lenses' started by stargate, Nov 12, 2013.

  1. stargate

    stargate Mu-43 Regular

    131
    Aug 14, 2013
    Greece
    OK, I just bought a used P20, and I noticed something peculiar. The lens keeps focusing when I move the camera around without me pressing the shutter button.
    Also, the choices I am given for AF are only AFS and Manual (no AFF and AFC). When I put it on Manual then it focuses with the focus ring, but on AFS it focuses with the shutter button half-press as well as on its own when I move the camera. Is this normal?

    By the way, I use it on a GX1.
     
  2. Darren Bonner

    Darren Bonner Mu-43 All-Pro

    May 1, 2013
    Poole UK
    Yes, your P20 sound like it's working fine, mine does the same.
     
  3. stargate

    stargate Mu-43 Regular

    131
    Aug 14, 2013
    Greece
    Thanks for the quick reply. That is reassuring but I wonder if this shortens the battery life.
     
  4. phl0wtography

    phl0wtography Mu-43 Veteran

    227
    Apr 15, 2011
    Considerably! AF is like the biggest battery drain next to the LCD, flash, and stabilizer.
    Just disable full-time AF, or what it's called with Panasonic bodies.
     
  5. Cruzan80

    Cruzan80 Mu-43 All-Pro

    Aug 23, 2012
    Denver, Co
    Sean Rastsmith
    Hasn't shortened mine "considerably". Maybe 60-75 shots less than usong full manual legacy lens. The focusing you are seeing is it trying to keep most of the scene relatively in focus. Because the entire element moves, if it is mostly there, it focuses much faster. The Oly 60 did that on mine as well, but much more so. Personally, I have found that if the camera is already pointed in the general section I am going to take a shot, it is almost as fast to loc focus as the kit lens. Less so if it has to start out traveling a decent distance.

    Sent from my LG-P769 using Mu-43 mobile app
     
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  6. meyerweb

    meyerweb Mu-43 Hall of Famer

    Sep 5, 2011
    My GH3 has a settings in the menus to control this focus activity, IIRC. I suspect the GX1 does as well. I'm not where my camera is at the moment, but look through the shooting and custom menus for focus settings. I'm pretty sure there will be a way to prevent it from AF'ing until you press the shutter release half way.
     
    • Like Like x 1
  7. stargate

    stargate Mu-43 Regular

    131
    Aug 14, 2013
    Greece
    Thanks everybody. I'll try to find something in the menus if possible

    OK I found it! It's called Quick AF. I set it to OFF and all is back to normal again.
     
  8. Hagane

    Hagane Mu-43 Regular

    88
    May 31, 2013
    Limburg, Netherlands
    I suspect that you had Quick-AF activated all the time, but lenses with internal focussing are much quieter. Maybe you just didn't notice that your other lenses were also focussing all the time? :wink:
    The deactivated AFF and AFC buttons are normal with the 20mm, focus speed isn't high enough to support these modes.
     
  9. stargate

    stargate Mu-43 Regular

    131
    Aug 14, 2013
    Greece
    I did have it ON all the time before, but when investigating the "strange issue" with the P20, I put my 14-42 on to check and it definitely did not focus on its own. That is why I thought that maybe the 20 was in trouble. Anyway now the Quick AF is off and the ghost in the machine is banished for good :)