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Inspire 1 video with minor jitter during yaw ><

Discussion in 'Inspire 1 Discussion' started by intelli, Jun 15, 2015.

  1. intelli

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    Is anyone else experiencing the slight jitters during yaw? I am yawing with the bird not the gimbal.
    Also, I uploaded the video in 4K but now it will only show 1080p. I checked when it was done uploading I had 4K and 1440 resolution to choose from. What happened to those 2 settings?
    Anyone kind enough to help a brother out? =D

    Thanks!
     
  2. 56speedster

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    Hi Intelli, Cool video and nice music. I notice jitter in the vertical movements as well even when you are descending. I am not an expert but it seems to be a processing artifact. Possibly the MicroSD card. What shutter speed are you using?
     
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  3. intelli

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    Hey thank you.
    I was using the sd card that came with the bird for this video recording at 4K 30fps and I believe i was using 1/60 shutter and 100 iso. You think maybe the sd card that came with it isnt fast enough?
    I just purchased a 64gb Sandisk extreme pro, but still havent had the time to try it out yet.
     
  4. 56speedster

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    That was one thought, I also bought the 64gb Sandisk extreme pro, I have had no issues with it, it is a highly ranked card. I assume you see the jitters in the unprocessed files off the card? Your camera settings sound right on the money.
     
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  5. 56speedster

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    I do see some jitters in my video as well. Making very slow pans seems to help lessen the jitter effect.
     
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  6. intelli

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    I have my expos lowered so my yaw is very slow already. urgh. the jitter in the video is really bothering me. lol
     
  7. 56speedster

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    I know what you are saying, I am the same way, always striving for a perfect smooth shot. It could be a firmware issue. Keep up the good work your video is great to watch. I will let you know if I hear any way to change settings to help.
     
  8. Carlsberg

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    Does ANYONE here have a LEVEL horizon?, (mine are like this video).
    I thought this was supposed to be a "professional" setup?
     
  9. Red Baron

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    Hi -did you manage to solve your video jitters? I'm having similar issues, Thanks, RB
     
  10. Mike Mas

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    In brief – the camera mounting on the Inspire is an absolute joke – been at this as long as anyone and “never” have I ever seen such a “Circus Act” in mounting a camera under a machine – the camera is constantly in motion which causes a number of problems.There is little doubt that DJI dropped the ball on this application. Mounting of the camera in this manner is a magnet for problems such as; jitter, vibration,Jell-O to name a few.

    In fact – the first per-release video I seen of an Inspire flying with that camera flopping around like it was falling off – I thought was a joke. A simple yet effective mod which I added my second flight is by using a few small tie-wraps to dampen the swinging motion of the camera – Begin with them lose and then tighten them a few clicks at a time until you see the lateral movement dampen out. This is just a fix - the actual dampening needs to be redesigned. However, this will improve performance as well as preserve both the gimbal motors and battery life. I have included a post below which I placed on the RC Group Forum for you guys to review!

    Thanks – Mike

    INSPIRE MOUNT.JPG

    I’m not finding fault with the quality or performance of the Inspire, the machine is a marked improvement and trendsetter in ARF aerial platforms. In addition, the tie-wrap mod is nothing new or unique either, modelers (myself included) have used everything from; liquid silicon to rubber bands to help correct dampening.

    Regardless of how happy we are with the Inspire there is always room for improvement – DJI is not a “Drone God” they make plenty of mistakes just like us. Keep in mind 95% of drone R&D is accomplished by pilots in the field like the very ones on this forum. Anyway you look at it DJI got the dampening of the Inspire dead wrong!

    To clarify myself – true lateral movement of a stable camera platform is not anything new – having spends years using Garrett’s Steadicam, we suffered constantly with lateral movement from running and stair shots and such where the result is not a shake but a smearing effect in the shot - this was later remedied with electronic camera lens.

    As we look at the Inspire’s unique problem – most pilots think its just lateral movement because think they see only in a lateral movement of the camera - when in fact this is this furthest from the truth. The center of the Inspires lens is located 4.25” below the platform, so as the camera shakes at a frequency of 1-3 times per second, the camera is actually moving in an arc from the mount. i.e. the camera is swinging from the mount and not sliding as it would on a rail for true lateral movement.

    This problem is know as a “Pendulum Movement” on each shake, the camera moves out of its horizontal plane because the 4” pendulum has considerable more movement on the bottom of the arc than it does at the top. This movement, which is changing the horizontal plane of the camera, is in turn picked by the sensors resulting in an instruction to the motor in an attempt to correct the movement. In other words - the roll motor is constantly at work in an attempt to move the camera back to its original horizontal plane on every swing. This is why its important to restrict the movement of the camera – it serves no purpose what-so ever to have the camera shaking under the platform, it only severs to further burden the processor and over-work the motors and make us look like jerks on the set! lol

    While it could very well be other factors – after I stabilized my mount with the tie-wraps (no lateral swinging motion visible) I’m now achieving two additional minutes of flight time – I feel part of this is attributed to the roll motor being at idle most of the time.

    Best Regards - Mike Mas
     
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  11. Red Baron

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    Helpful...thanks Mike. Assume the SD card upgrade was a red herring then?
     
  12. Mike Mas

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    Thanks for the reply – you know - when I flew FAI competition all us guy’s dream was to have two machines that flew identical which of course we could never do, we got them close but seldom would you ever go to a meet with two machines that flew the same. The point I’m getting at it seems every machine is a little bit different, some are smooth some vibrate etc. Mine was embarrassing for me to fly in public.

    Needless to say, anyone could see the gimbal mount on the Inspire was broken – for me the old provervial tie-wrap trick worked wonders, there is about the same movement on the camera as my Phantom 3 which works great.

    Here’s the problem with the Inspire; the camera (center of lens) hangs down 4.5” under the machine where the Phantom camera is only 2 5/8” below the machine.

    The Inspires gimbal mount width is only 1 ¾” wide where the width of the Phantom mount is 4.5” wide – this width is what supports the camera from lateral movement. What makes matters even worse, is the Inspires camera and gimbal weigh considerable more than the Phantom so there is more pendulum weight for the mount to support.


    Regards – Mike
     
  13. sirnikolas

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    Cheers Mike. I'm gonna use the zipps too.
     
  14. The Editor

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    2 extra minutes flight time by attaching two zip ties?.... Are you sure about that?

    Curent draw for the X3 is 750/900mA (the latter when moving/correcting) - that is distributed among the three brushless motors for the three axis so we can assume 50mA for the roll motor under load.

    The Inspire use around 275mAh per minute (in hover) - more in climb out.

    For you to 'aquire' an extra two minutes of flight time utilising and depleting the same percentage of pack you would need to be saving circa 600mah of power through the zip tie mod.
     
  15. Mike Mas

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    If you think the gimbal does not draw very much current for station keeping just turn your inspire on and just sit on the table and watch just how quickly the battery depletes - as I mentioned, each machine is different - my camera shook 100% of the time so it took considerable current to stabilize it, yours might be different.

    I use a number of hand held 3 axis gimbal devices and if the camera is not balanced you can feel the motors constantly buzzing to hold the camera, on these devices an unbalanced camera will quickly reduces your operation time over 25%.

    Regards
     
  16. The Editor

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    Hi Mike, I am not doubting the fact the gimbal consumes power (obviously it does to be able to do its job) but a gimbal has static current and dynamic current.
    Static is where it is literally just applying sufficient power to stabilize the gimbal in situ. Dynamic current is where it is working hard and actively applying reverse thrust to counter abrupt movements etc. The X3 consumes VERY little power - 750mA static and 900mA dynamic so only 150mA difference between rest and full power This would be shared between all three axis/motors during corrective movements so circa 50mA additional to the roll axis during full force/rate of change.

    This does not seem sufficient to afford you an extra 2 minutes of flight time based on my calculations.
     
  17. Mike Mas

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    Thanks for the reply - keep in mind unlike motion from flight which is detected and quickly corrected this is a constant pounding motion in opposite directions, this type of movement is totally unusual for a gimbal and therefore taxes both the motors and battery usage.

    Do the math - 900 mA is a constant 1 amp draw on the battery for 15+ minutes. Also keep in mind the same genius's that are giving you these "Ideal" specs are the same ones who released possibly the worst gimbal ever on a drone. It puzzles me why the current is of such importance to you when your gimbal is falling off your machine!
     
  18. The Editor

    The Editor Moderator
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    I DID do the math, which is why I questioned your claim of an extra 2 minutes of flight time.
    The "Math" as you put it doesn't add up. You simply do not save sufficient power from preventing oscillation of the roll axis to give you 2 extra minutes of flight.
    The reason the current is so important to me is because your calculations are flawed.
    I will watch out for my gimbal falling off my drone and be sure to catch it as it falls - thanks.
     
  19. johnmont250

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    jeez, your gonna beat this dead horse here too?

    ridiculous. dji has the best stabalization. period.
     
  20. Mike Mas

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    Ok 1 min do you feel better now?

    Read the posts - almost everyone is crying about jitter, jello, and vibration - DJI went backwards 2 years with the Inspire camera and mount - the Phantom 3 still holds the reign of being the best RTF platform for a third of the money.