Weird Oscillation while holding the top handle of a M10 (C300PL+Epic)

Discussion in 'MōVI M10' started by Devon Campbell, Oct 8, 2013.

  1. Devon Campbell

    Devon Campbell New Member

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    So something weird happens. I set my gains so there is no oscillation while on the stand and holding the long bar. However when I pick it up by the top handle it starts to Oscillate. It goes way the second I tough (not even grab) one of the side grips.

    I did some trouble shooting and noticed that my pan gain was high and turned it right down (eg went from 90-40), I did the same with with the other gains at the respected gain levels and nothing changed. I'm just wondering if anyone has encountered the same issue or if I am doing something wrong? I've tried different cameras the c300pl and epic with a Zeiss 24mm prime and required power, re-balanced the camera and adjusted gain levels.
     
  2. Devon Campbell

    Devon Campbell New Member

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    of and yes I did read the manual, it does say that the top handle is the worst point for the pan axis, I'm trying to figure out why?
     
  3. Greg Hughs

    Greg Hughs New Member

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    I had oscillation issues and found that my Pan Window and Smoothing were set to 0. At Tabb's request, once I reset those back to 5-ish, the oscillation went away.
     
  4. Gary Haynes

    Gary Haynes Administrator
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    Devon try backing down the pan by 10 or so. The settings or pan are a bit different if you hold just the center handle. Also dependent on camera weight.

    And Greg's note also is good advice.
     
  5. Devon Campbell

    Devon Campbell New Member

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    Yeah backing down the pan gain does work, thanks! Just still wonder why it goes away once you touch one of the side arms, even with just a finger.
     
  6. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Devon:

    The MōVI is quite a mechanically complex marvel and I suspect that the phenomenon is that it has lots of different natural resonant frequencies -- and frequencies that change depending on where you hold it because your hands are inevitably acting as dampeners. I leave it to those with more recent Physics and Mechanical Engineering knowledge to describe it in more detail, but the things I've noticed are:

    1. If you adjust the Stiffness for no oscillation in the cradle, be sure to pick the MōVI up, both by the top handle and the side handles to observe the performance that you're actually going to get on set.

    2. If you do get oscillation or buzzing, adjust the Stiffness and/or the Expert Gyro/Output Filter until it stops -- and then be aware that you've probably "gone too far" and that you need to increase the Stiffness back up a bit -- the downward journey seems to overshoot a bit to make the oscillation/buzzing stop, takes you unnecessarily low.

    3. You can use the Chart option (I use the Android version of the MōVI app), to see if there is any oscillation going on -- it shows up as "lumps" in the lines, or just rest your fingertips as lightly as you can on each of the axes' motors in turn (or rear transverse boom). You can feel it, even if you cannot hear the oscillation.

    4. The natural resonance of the system changes depending on what is mounted and where, so be prepared to finesse the Stiffness/Expert settings as required. Obviously that's true if you change cameras and lenses, but I wouldn't be surprised to see changes if you put a zoom lens on the camera. In my experience, these adjustments are no big deal, take only a few seconds, and you can carry on a conversation while you're doing it. :)

    Anyway, those are my experiences. Hope it helps.
    Andy.
     

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