Gimbal Motor Overload and shaky footage
3024 11 2020-1-17
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Tactical Trvlr
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I previously posted on this forum trying to explaine the problem i've been experiencing with my MM. I made this video in an attempt to better explain the porblem nd look for a possible solution. I thought I had corrected the issue by changing props, recalibrating everything, refreshing firmware, changing memory cards, but nothing has been successful. I have DJI refresh and have opened a case, not to sound like a jerk, but comunication with DJI has been very difficult due to language barriers. I dont think they understand what i'm asking and I certainly am having truoble understanding what they are asking me to do.
I can return the drone to Best Buy and get a replacement at no cost. I have tried unsuccessfully to find out from DJI if my DJI Refresh can be transfered to the new drone. Still no answers, just a lot of strange emails that seem to ignore my question. Any ideas or suggestions appreciated. Thanks


2020-1-17
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Tactical Trvlr
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Hey DJI i'm just going to return the Drone to Best Buy for a replacement. Can you advise if my DJI Refresh is transferable since this drone is clearly defective?
2020-1-17
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DJI Natalia
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Hi Tactical, we are so sorry to hear about the unpleasant experience that you encountered with our support team. We have managed to get your ticket number via your forum account, we'll forward the situation to the related team to investigate and keep improving.
For the DJI Care Refresh, it is transferable based on your situation, please contact djicare@dji.com and provide the replacement evidence, our team will help you with that.
2020-1-17
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Geebax
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I have a couple of things for you, first is that the wobble is called 'Jello Effect', and it is caused by vibration of the camera. You cannot fix it by calibrating the gimbal, the compass or anything else. And the SD card has nothing to do with it either. Some people will say it can be fixed with an ND filter, and that is wrong too. The most common cause is out of balance props vibrating the whole aircraft, look for nicks or dings or bits broken off.

Second, don't take off from the car park. That one looks to be bitumen, but some are concrete, and concrete most often has steel rebar in it. The rebar can badly affect your compass. Take off from grass if you can.


2020-1-17
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Tactical Trvlr
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DJI Natalia Posted at 1-17 20:14
Hi Tactical, we are so sorry to hear about the unpleasant experience that you encountered with our support team. We have managed to get your ticket number via your forum account, we'll forward the situation to the related team to investigate and keep improving.
For the DJI Care Refresh, it is transferable based on your situation, please contact  and provide the replacement evidence, our team will help you with that.

Thank you for the response.
2020-1-18
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Tactical Trvlr
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Geebax Posted at 1-17 20:31
I have a couple of things for you, first is that the wobble is called 'Jello Effect', and it is caused by vibration of the camera. You cannot fix it by calibrating the gimbal, the compass or anything else. And the SD card has nothing to do with it either. Some people will say it can be fixed with an ND filter, and that is wrong too. The most common cause is out of balance props vibrating the whole aircraft, look for nicks or dings or bits broken off.

Second, don't take off from the car park. That one looks to be bitumen, but some are concrete, and concrete most often has steel rebar in it. The rebar can badly affect your compass. Take off from grass if you can.

Thank you for the advice. I returned my drone to Best Buy and they are sending a replacement. I think the gimbal itself was defective. I could feel it vibrating when I picked up the drone while it was powered on. As for the suggestion about taking off on grass only, I did not know that. Thank you for the info when my new drone arrives I will take off from grass whenever possible.
2020-1-18
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InspektorGadjet
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Let us know when you get a replacement!
2020-1-18
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Geebax
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Tactical Trvlr Posted at 1-18 03:02
Thank you for the advice. I returned my drone to Best Buy and they are sending a replacement. I think the gimbal itself was defective. I could feel it vibrating when I picked up the drone while it was powered on. As for the suggestion about taking off on grass only, I did not know that. Thank you for the info when my new drone arrives I will take off from grass whenever possible.

I normally suggest that people examine the aircraft when it is switched on to see if they can detect any vibration while it is stationary, but you seem to have done that.
2020-1-18
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lannes
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Geebax Posted at 1-18 13:14
I normally suggest that people examine the aircraft when it is switched on to see if they can detect any vibration while it is stationary, but you seem to have done that.

What would be the reason why you see "jello" more in some AC's than in others of the same design.
Is the effect always there to the same extent and we just don't notice it or are there conditions that exacerbate it e.g. vibrations due to propeller imbalance ?

I read you can reduce the jello issue by increasing the fps of the video, improving gimbal dampening etc. does this work ?
Does it have anything to do with the quality of the CMOS sensor used, could there be manufacturing differences/ tolerance and QC issues ?

Won't the OP have the same issues with a replacement MM if it's a limitation of the CMOS rolling shutter design ?

2020-1-18
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Geebax
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lannes Posted at 1-18 14:42
What would be the reason why you see "jello" more in some AC's than in others of the same design.
Is the effect always there to the same extent and we just don't notice it or are there conditions that exacerbate it e.g. vibrations due to propeller imbalance ?

We should clear up some misconceptions before answering your questions. There is a very common tendency by some to call the stuttering motion during a camera pan 'jello', when it is not. That is a completely different effect and does not have the same cause, or cures.

So, increasing frame rate will not cure jello, as it is not related to frame rate in any way. Jello is called that because the middle of the image looks like a bowl of jello or jelly to non-Americans. Likewise, improving gimbal dampening does not cure it much either, as the dampening moments are designed to minimise large scale vibrations in flight, and the design is 'tuned' to the gimbals size, weight and forces.

And no, jello has nothing to do with the quality of the CMOS sensor, the only thing in the sensor design that would eliminate it is the provision of a global shutter. Another common urban myth that has no truth to it is that adding a filter will cure jello. It most certainly will not.

Yes, the OP could get the same problem if he/she exchanges the MM for another.

I wrote a piece about jello some time ago: https://forum.dji.com/thread-34408-1-1.html


2020-1-18
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Tactical Trvlr
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Geebax Posted at 1-18 16:26
We should clear up some misconceptions before answering your questions. There is a very common tendency by some to call the stuttering motion during a camera pan 'jello', when it is not. That is a completely different effect and does not have the same cause, or cures.

So, increasing frame rate will not cure jello, as it is not related to frame rate in any way. Jello is called that because the middle of the image looks like a bowl of jello or jelly to non-Americans. Likewise, improving gimbal dampening does not cure it much either, as the dampening moments are designed to minimise large scale vibrations in flight, and the design is 'tuned' to the gimbals size, weight and forces.

Well my replacement MM arrived today, unfortunately due to some wind in the forecast I wont be able to take it for a test flight for a couple of days.

I really appreciate all of the valuable information from everyone in this thread. Especially from Geebax, who clearly knows his stuff about these things.

Thanks
2020-1-21
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Geebax
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Tactical Trvlr Posted at 1-21 15:15
Well my replacement MM arrived today, unfortunately due to some wind in the forecast I wont be able to take it for a test flight for a couple of days.

I really appreciate all of the valuable information from everyone in this thread. Especially from Geebax, who clearly knows his stuff about these things.

You are most welcome.
2020-1-21
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