Balancing the Epic / Forward Creep

Discussion in 'MōVI M10' started by Nick Pujic, Oct 7, 2013.

  1. Nick Pujic

    Nick Pujic New Member

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    Has anyone else had a reasonable amount of trouble when roll balancing the Epic (side handle and red volt system)?
    It seems that the mass density within the camera isn't uniform, so when tilted / rolled, the CG changes. Is that right or am I that far off?

    Also, after balancing as best as possible, turning the Movi on, the tilt wants to go all the way forward, even with ni input from the joystick. This causes the camera to tilt too much down.

    I apologize for the noob questions, just trying to get 'er all figured out.
    Thanks so much in advance,

    Nick
     
  2. Tabb Firchau

    Tabb Firchau Administrator
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    Nick, Are you able to shoot a quick video? That would be most helpful

    Thanks

    Tabb
     
  3. Nick Pujic

    Nick Pujic New Member

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    Tabb thanks so much; video link below. The tilt balance was set, but the roll balance seems bottom heavy. The camera always wants to right itself, no matter which way I roll the gimbal. Any ideas?

    Password is roll


    Thanks again!
     
  4. Mike Duval

    Mike Duval Member

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    An old R/C aircraft trick to establish the center of gravity is to place the object you want to balance on a round pencil. In this case, put the pencil under the QR plate for the MōVI then roll the unit back and forth to establish where the unit's fore/aft CG is. That would be the first place I'd start. I agree with Tabb though that a video would help.

    Mike
     
  5. Brad Meier

    Brad Meier Active Member
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    Your roll balance is good and probably as close as you'll get with that much weight. The roll motor will have no problem with roll balance being just a little off.
     
  6. Mike Duval

    Mike Duval Member

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    I think you need to raise the vert tilt adjustment and slide the camera slightly on the tilt front/back adjustment. Raising the CG on the vert tilt adjustment will put you in a much tighter balance envelope on the front/back adjustment plate but should null out the bottom heavy tendency you're seeing.

    Mike
     
  7. Brad Meier

    Brad Meier Active Member
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    Mike, Raising tilt only affect the tilt adjustment and will have no effect on the roll.
     
  8. Casey McBeath

    Casey McBeath Member

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    Brad, thank you for the input. We had similar issues with the roll when shooting an Epic for the last week. My first thoughts were similar to what Mike D. suggested, as it always rolled back to "center" as though it were bottom heavy. We've since torn it all down since the shoot concluded so more tinkering was prevented.

    As Brad mentioned a few posts up, I merely lived with it and the MoVI handled it fine. I began using the charting function to test my balances, assuming that at rest, the more a motor was working, the further off the balance was. The Roll Motor had a bit of activity at rest, but seemed equally taxed when testing to either side. Ultimately we didn't suffer from it and work continued as planned.
     
  9. Mike Duval

    Mike Duval Member

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    Hmmm....that thought process made sense in my head when I typed this. Could you relate this to a Steadicam balancing type situation? I know the goal there is to achieve a slightly bottom heavy balance scenario. Close to that limit its amazing just how small of a change takes you from top to bottom heavy.

    I know on the M10 the goal is to be totally neutral so the motors have to exert little if any power in achieving a level attitude. Would this type of balance indicate that there might be a bit more that could be eeked out? Obviously the roll balance being bottom heavy isn't the worst thing for keeping a level horizon though. Sadly, I haven't been able to mount an epic/scarlet on the M10 yet so I can't say that I've got any direct experience near the M10's limits. Thanks for the insight.
     
  10. Christopher Barrett

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    Same deal. I find it impossible to perfectly balance roll AND tilt with my Epic. No issues doing that with a lighter camera. In any case, once I have it as close as I can get the motors seem to handle the rest. Is this accurate procedure?

    CB
     
  11. Nick Pujic

    Nick Pujic New Member

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    That makes a lot of sense guys. Thanks for all of your input, and speedy response. I balanced it as best as I could, turned it on, trimmed it out, and it works great! Unbelievable piece of gear.

    Well done Tabb & team!
     
  12. Lliam Worthington

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    Couple of questions, I'd really appreciate some input on.

    First, just wanted to be sure that to balance their Epic/Scarlets with sidehandle, by necessity everyone is sliding the cage off centre at the back where the MOVI logo and motor is? (Similart to how it comes off centre in the box on shipping)

    What level of torque/stiffness are people getting with their balances?

    I've been experiencing the same quirks with roll balance expressed above, the better the balance, definitely the smaller the trims required though I'm finding.

    Thx guys

    Best

    Lliam
     
  13. Mike King

    Mike King Member

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    I was having most of the problems everyone has been talking about. I'm using an Epic with side handle and Zeiss CP 2's on front. When I first put it together everything was spinning out of control like a scene from "Gravity". It now sits perfectly still with no power on.

    The first thing I did was to shift the cage to the left (facing the camera). I was also having the roll problem where the camera was always righting itself. For me it was a case of it being bottom heavy and I raised it up so that the Red logo is about even with the tilt motor. This for me was the most time consuming and frustrating adjustment as even the smallest amount made a big difference. The front to back balance now goes pretty quick when I attach the camera.

    Cheers,

    Mike
     

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