A "bouncy" operating problem

Discussion in 'MōVI M15' started by Peter Sandler, Feb 24, 2016.

  1. Peter Sandler

    Peter Sandler New Member

    Joined:
    Feb 24, 2016
    Messages:
    4
    Likes Received:
    1
    Hey guys. Had M15 rigged with Alexa Mini and some primes (nothing real heavy, some superspeeds and Pancros). I am new to the gimbal game - so pardon me if the question is stupid. I balanced it correctly, it seemes, but had an issue that I really really can see every step I make, not as smooth as I saw from some videos on Vimeo or some tests online. Is that normal? I understand that's the motion that Movi can't really compensate more or less, but does this footage look ok?.. Thanks!

    The test: https://vimeo.com/156607823/25242a5c90
     
  2. Brad Meier

    Brad Meier Active Member
    Staff Member

    Joined:
    Aug 14, 2012
    Messages:
    749
    Likes Received:
    66
    Your tilt stiffness could be higher from the looks of the tilt movement. Whats your setting? You should be able to get 100 or more on that setup.
     
  3. Peter Sandler

    Peter Sandler New Member

    Joined:
    Feb 24, 2016
    Messages:
    4
    Likes Received:
    1
    Thanks for the advice! I will check tomorrow when I'm back in the rental. If I'm correct, it was about 80. So tilt stiffness is what should hold in place that particular movement?
     
  4. Peter Sandler

    Peter Sandler New Member

    Joined:
    Feb 24, 2016
    Messages:
    4
    Likes Received:
    1
    Also I struggled to understand the Tilt Axis balancing a bit - as it had full cage )no top plate on that Mini, though). Do I leave the bottom of the cage in the lowest possible position, or do I shift everything sort of towards the middle and then balance it on the middle of the tube, not touching the outer toggles (ones holding bottom and top of the cage?)?
     
  5. Brett Harrison

    Brett Harrison Active Member

    Joined:
    Apr 7, 2013
    Messages:
    299
    Likes Received:
    40
    There's definitely a shift in vertical perspective going on.

    There's more to it than this, but practice with a glass of water. Once you can move around your house without it moving around too much, you will have gained the muscle memory skill needed to move a gimbal through space in a straight line. The 'ninja walk'.

    It's mostly about how you walk as well as allowing your arms to boom slightly to compensate for each step. I find holding the handles by my fingertips helps for certain shots.
     
  6. Graham Futerfas

    Graham Futerfas Well-Known Member

    Joined:
    Oct 19, 2015
    Messages:
    1,227
    Likes Received:
    239
    Hi Peter. Do you have a support vest, like a Ready Rig or an Armorman? Or are you planning to hold that rig up with your bare arms?

    In addition to walking smoother, I'm often having to make adjustments to settings in order to reduce footsteps -- more stiffness from the motors, less tension from my Ready Rig. There are also 4th axis stabilizers out there, but they get expensive.

    For most cameras, I like to set my cage up so that the bottom of the cage is all the way down, and then the top of the cage comes down to wherever the top of the camera is (to hold the top slider plate). This leaves some space on top of the rails for me to put my Focus receiver and sometimes the Video transmitter, usually strapped on with Bongo Ties.

    Then you can adjust the Tilt Vertical CG balance by moving the whole cage up or down, loosening the 4 levers in the middle of the cage, by the motor. I usually do this by tilting the camera all the way up, so the lens is facing the ceiling, and then you can see which way the camera wants to fall.

    If you watched Tabb's older video tutorial on this, I see why you're confused because he adjusted Vertical balance by sliding the bottom of the cage up. On the M15, you'd use the 4 middle levers and move the whole cage and camera.

    Good luck and have fun,
    -Graham
     
  7. Brett Harrison

    Brett Harrison Active Member

    Joined:
    Apr 7, 2013
    Messages:
    299
    Likes Received:
    40
    Just a couple of notes about balance of the rig vs. visible stepping.

    The gimbal only takes care of rotation, and stepping is a vertical and somewhat lateral shift. Unless you have very low stiffness settings your settings won't add to the effects of stepping.

    Try balancing to perfection then picking up the rig and walking around with it - with it turned OFF. If the rig basically stays put then you're walking well, if it moves all around then even though the motors are counteracting the minor rotational effects of stepping, the motors are the least of your worries.

    The COG determines the position of the top of the cage, though you can shift the height of the side bars down to make sure they clear the pan motor (if your setup allows you to get that far away). To add distance from the pan motor you can add weight on the top of the cage to bring the COG up thus bringing the camera package down overall. This is certainly diminishing returns though.

    There's a jolt rejection feature in the new software if you have to really run fast with the rig thus causing unavoidable disturbance in the vertical and lateral position of the camera trajectory.

    If you don't have a spring-loaded vest setup you can still make a poor man's Walter Klassen Slingshot to remove stepping and fatigue. There's a recent photo of such a setup in my instagram feed (link in sig).
     
  8. Peter Sandler

    Peter Sandler New Member

    Joined:
    Feb 24, 2016
    Messages:
    4
    Likes Received:
    1
    Guys, thanks so much for all the notes - I made a whole list of improvements and will go back into rental for another day of tests to see if I can make this piece of gear work for me. Thanks so much!
     
    Brett Harrison likes this.

Share This Page