Is This Dropped Frame(s)? Or Bad Piloting?

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A few weeks back I got some sort of "jump" in the footage where the camera angle changes abruptly. I am not sure if this is frames that were "dropped" (i.e., not recorded to the SD card), or whether the AC was just buffeted by the wind (I was using DJI GO4 in GOS mode on my P4P), or just bad piloting on my part.

The video loops four times in case you are wondering (the jump only occurred once).


For the SD card, I am using a sandisk Extreme Plus V30 (32GB)

I was shooting at 4K 60fps.


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Looks like it dropped a few frames. Hopefully, a rare occurrence. I don't recall it happening to me, although I have had a frame freeze for about a second.
 
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You have a good card, so that shouldn't be the problem. I have a P4P and never had that happen. Definitely not piloting error. You might try a different Class 3 card to see if it happens again. Good luck!
 
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'SanDisc extreme pro' I'm using (red and black). Never failed. Yours should be good too.
 
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I don't think it was dropped frame, it looks like the gimbal or drone jumped a bit. Kind of like when the P4P gimbal will flip 90 degrees when flying crosswind to the right into a strong wind. IMHO
I could be wrong of course.
 
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I extracted the video and slowed it down to take a closer look. You guys are right. This was some kind of jolt or shudder in the gimbal/airframe. If it was merely dropped frames, you would see a continuation along the same line. Instead, the continuation is at a different angle. As Martin noted, the gimbal pitched slightly upward. It was quick, though. The entire jolt occurred within the space of one frame - one thirtieth of a second.
 
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Thanks to everyone who has replied so far.

This is kind of curious to me that there would be a "jolt" to the aircraft.

Is it most likely due to a wind gust?

I have flown three or four missions since then and haven't noticed any odd behavior, but I have flown only two missions since then that involved shooting video (the rest were stills), and there doesn't seem to be any issues in the 20-minutes of video from that subsequent missions.

Does this just fall in to the category of "stuff happens"???

I admit that I do tend to be a "nervous" pilot and there is a very real possibility that I accidentally bumped the gimbal pitch wheel. although I thought I had put in a lot of expo on all the controls (included the pitch wheel), so I wouldn't expect to see it jump like that.

Thanks in advance for any other thoughts.
 
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I don't think it was dropped frame, it looks like the gimbal or drone jumped a bit. Kind of like when the P4P gimbal will flip 90 degrees when flying crosswind to the right into a strong wind. IMHO
I could be wrong of course.
Thank you for your input. I had never heard of that condition about the gimbal flipping 90 degrees. It was a bit windy up there.
 
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I extracted the video and slowed it down to take a closer look. You guys are right. This was some kind of jolt or shudder in the gimbal/airframe. If it was merely dropped frames, you would see a continuation along the same line. Instead, the continuation is at a different angle. As Martin noted, the gimbal pitched slightly upward. It was quick, though. The entire jolt occurred within the space of one frame - one thirtieth of a second.
Thank you for taking the time to break down the footage.

Actually, I was shooting at 60fps, not 30fps (I slowed it down to 30fps on the timeline), so the holt was even faster than that.
 
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'SanDisc extreme pro' I'm using (red and black). Never failed. Yours should be good too.
Thank you for the confirmation. I am still relatively new to the P4P and shooting 4K 60fps (I had always shot with a P3A at 2.7K 60fps (IIRC), and those cards had always worked fine in the P3A. But the bitrates are significantly lower, from what I remember.
 
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You have a good card, so that shouldn't be the problem. I have a P4P and never had that happen. Definitely not piloting error. You might try a different Class 3 card to see if it happens again. Good luck!

Thank you for the reply and thanks for whishing me good luck. I am the kind of pilot who can use all the good luck he can get!!!
 
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Thanks to everyone who has replied so far.

This is kind of curious to me that there would be a "jolt" to the aircraft.

Is it most likely due to a wind gust?

I have flown three or four missions since then and haven't noticed any odd behavior, but I have flown only two missions since then that involved shooting video (the rest were stills), and there doesn't seem to be any issues in the 20-minutes of video from that subsequent missions.

Does this just fall in to the category of "stuff happens"???

I admit that I do tend to be a "nervous" pilot and there is a very real possibility that I accidentally bumped the gimbal pitch wheel. although I thought I had put in a lot of expo on all the controls (included the pitch wheel), so I wouldn't expect to see it jump like that.

Thanks in advance for any other thoughts.
Your flight record would show if there was pilot input. But I think it's too sudden and too brief a movement to be either pilot input or a wind gust. In theory, your gimbal could impact with a bee or some large insect and it might have that effect. Other than that, it's got to be something caused by the drone.
 
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Very likely this is not the gimbal issue nor the pilot.
It must be something with the read write process. I would try with a faster card.
 
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Very likely this is not the gimbal issue nor the pilot.
It must be something with the read write process. I would try with a faster card.
Ha! We have as many opinions as we have pilots. Not to mention, me changing mine.
There are no skipped frames. The camera appears to have changed it's angle: A short, sharp 'jolt' that tilts it slightly upward.
 
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Thanks to everyone who has replied so far.

This is kind of curious to me that there would be a "jolt" to the aircraft.

Is it most likely due to a wind gust?

I have flown three or four missions since then and haven't noticed any odd behavior, but I have flown only two missions since then that involved shooting video (the rest were stills), and there doesn't seem to be any issues in the 20-minutes of video from that subsequent missions.

Does this just fall in to the category of "stuff happens"???

I admit that I do tend to be a "nervous" pilot and there is a very real possibility that I accidentally bumped the gimbal pitch wheel. although I thought I had put in a lot of expo on all the controls (included the pitch wheel), so I wouldn't expect to see it jump like that.

Thanks in advance for any other thoughts.
Just wondering if you had a filter or sunshade fitted to the camera? The additional weight on the lens can allow wind gusts to overpower the gimbal motors. This happened to me big time once when I fitted a light weight sunshade which really caught the wind. The video feed shown such a crazy shift that I initially thought that my P4 was on the way down.
 
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Your flight record would show if there was pilot input. But I think it's too sudden and too brief a movement to be either pilot input or a wind gust. In theory, your gimbal could impact with a bee or some large insect and it might have that effect. Other than that, it's got to be something caused by the drone.

Thank you for the elaboration. If I have time over the upcoming weekend I will dig through the flight record just to double check.
 
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Just wondering if you had a filter or sunshade fitted to the camera? The additional weight on the lens can allow wind gusts to overpower the gimbal motors. This happened to me big time once when I fitted a light weight sunshade which really caught the wind. The video feed shown such a crazy shift that I initially thought that my P4 was on the way down.

Thanks for the note. Actually, no sunshade and no filter (except for the default UV filter that comes with the P4P camera).

I have been thinking of getting a lens hood / sun shade just because I had some footage ruined recently where the shadows from the propeller blades were being caught by the camera. Good to know about the potential for them to get caught by the wind.
 
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A few weeks back I got some sort of "jump" in the footage where the camera angle changes abruptly. I am not sure if this is frames that were "dropped" (i.e., not recorded to the SD card), or whether the AC was just buffeted by the wind (I was using DJI GO4 in GOS mode on my P4P), or just bad piloting on my part.

The video loops four times in case you are wondering (the jump only occurred once).


For the SD card, I am using a sandisk Extreme Plus V30 (32GB)

I was shooting at 4K 60fps.


View attachment 124012
That looks like dropped frames to me.

FWIW, I use the Extreme Pro 128GB and 64GB cards in my P4P. In years of flying and hours upon hours of video I can't ever remember a single dropped frame.

Also worth noting; My new job requires hours upon hours of 4K GoPro video (Hero8). Of the 4 cameras, 3 had Extreme Pro cards and one had the Ultra. Cam4 would randomly shut down after about an hour about half the time. Replacing the Ultra with an Extreme Pro cured the problem completely. The Ultra, like the Extreme Plus, is an A1 card. The Extreme Pro is an A2. That's all I use now in everything. They have been extremely reliable.

D
 

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