Dual adjustable plates,Sony 760, and flipping the picture

Discussion in 'Cameras' started by Dave King, Apr 16, 2013.

  1. Steve Maller

    Steve Maller UAV Grief Counselor

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    Andy, I'm nervous about building more flexibility into the mounting system, as my intuition tells me that things like the flexible rubber standoffs may actually amplify the movements of the copter.

    I jut re-did the mounting contraption with some proper spacers that I got from AmazonSupply, along with screws to match.
    The parts are:
    https://www.amazonsupply.com/dp/B005A0HSUU
    https://www.amazonsupply.com/dp/B009YLCWP2
    The order total was about $26, and I've got lots of spares.
    Here's what it looks like now. I kinda like the black screws.
    IMG_6715.jpg
     
  2. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    You may be right....but my logic said that if the copter zigs, then the mass of the camera (at least according to Newton), would tend to stay put rather than zig or zag... but I've just been shooting some test footage so I'll me check it out and I'll let you know.

    Aha. You've discovered the Amazon Supply candy store! :)

    Andy.
     
  3. Steve Maller

    Steve Maller UAV Grief Counselor

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    I never did well in physics (explains why I ended up in software), but with an ordinary "body in motion" thing, that wouldn't matter. But what I find with the copters is that the aerial stability of the airframe itself ends up being compromised by excessive camera movement. Therefore, the gimbal might be stable, but if that copter starts oscillating, you're in trouble WRT camera stability. Motion doesn't only move from copter->gimbal->camera, but sometimes goes backwards (camera->gimbal->copter).

    Does that make sense?
     
  4. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    I'll post some of the test footage and you can be the judge! <evil grin>

    You're right that the vibration might go both ways, but you're not going to have the Sony vibrating at high frequency -- it's essentially a mass-dampener -- whereas the motors/props are humming at several kilohertz complete with sub-harmonics.... So I suspect the correct logic is to stop the camera vibrating and let the airframe hum away....

    But, as I say, I'm just editing the footage now cutting out the junk. I'll try and get it done tonight but it's AVCHD footage so, as a perverse touch, I'm editing in Adobe Premiere Pro CS6 -- where I normally editing in Final Cut Pro, so some of the basics are "challenging." Like, "how do I move a frame at a time...." (I'm used to having the arrow keys do that....) I've tried setting the Keyboard interface to FCP 7, but it doesn't look like all of the keys get re-mapped properly.

    Andy.
     
  5. Steve Maller

    Steve Maller UAV Grief Counselor

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    I just shot a little test footage with the setup I described.
    Balanced my props, too.
    Very smooth IMHO.

     
  6. Gary Haynes

    Gary Haynes Administrator
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    Steve that looks pretty Smooooooth. Was it with the BOSS system turned on? If you ever get the chance can you do a pair of flights, same flight test pattern with the BOSS turned on and then off? Coming from the stills world all of the manufacturers say to turn IS off if you are on a tripod. I've always wondered if the same logic would hold true when using the Radians.
     
  7. Steve Maller

    Steve Maller UAV Grief Counselor

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    Good point.
    Actually, there are three modes I'd like to test. BOSS on, ordinary stabilization on, and stabilization off completely.
     
  8. Joe Azzarelli

    Joe Azzarelli Active Member

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    dave
    In your post (#10) it seems your front horizontal tube is not parallel with your rear tube, probably because the booms are 'torqued' wrt to each other. Also, it seems the adjustable rails are not parallel either. I see you are using the camera weight to offset the weight of the tilt servo and gears, which is less than idea. Finally, the booms are going to have to be tilted up to get the tilt axis passing through the roll axis to get the roll perfectly balanced.

    I am not being critical but want to point out that all of these things will affect how well the gimbal is going to work for you.

    The attached doc needs a little updating but hope it can help.

    Good luck!

    Joe
     

    Attached Files:

  9. Joe Azzarelli

    Joe Azzarelli Active Member

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    I am using these as well and they are working great.
     

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