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This this pan judder normal?
587 8 2018-8-19
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PandaCheese
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Could use some expert eyes to judge whether my MPP's camera/gimbal has  too much pan-induced judder. I shot a video of a slow pan (360 degree in  about 1:05 min) in 1080@30fps in auto (so shutter was between  120-240ish). The judder is most visible starting around the 35s mark  when panning over some apartments on a hill. Please watch video in full  size to see clearly.



I know there has been innumerable threads on this topic but is there  something that shows what an unprocessed pan shot should look like on  known good hardware?                                                
2018-8-19
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Woe
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Looked to me like the camera was auto focusing and the exposure adjusted because of changing light.
Don't think it's hardware, Maybe try shooting manual and using a Nd filter.
2018-8-19
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Bekaru MP UAV
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Does not look like pan induced shudder to me. Woes reply sounds like a better possibility.
2018-8-19
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DJI Stephen
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Hi there, thank you for reaching out. Regarding your concern Upon checking it seems just normal as what the previous post as well it would be better to use an ND filter then give a try to lock the auto exposure setting on the DJI Go 4 app.
2018-8-19
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Paul_IA
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As you're rotating, you can see the colors changing so I think this is just auto exposure doing it's thing. Give a look at some of the YT videos that show different methods of using manual exposure and see if that fixes your issue.
2018-8-19
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PandaCheese
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Appreciate the replies but my question wasn't about exposure but the pan-induced judder or jittery, shifting images. It's most visible when panning across regularly shaped polygons like buildings, with edges perpendicular to the horizon. In my footage you can see it best starting around the 35s mark, but please you need to watch it in fully quality to see it.
2018-8-19
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Mike Warren
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PandaCheese Posted at 2018-8-19 14:36
Appreciate the replies but my question wasn't about exposure but the pan-induced judder or jittery, shifting images. It's most visible when panning across regularly shaped polygons like buildings, with edges perpendicular to the horizon. In my footage you can see it best starting around the 35s mark, but please you need to watch it in fully quality to see it.

I see the jitter through most of the video, although it's most prominent at around 14 seconds and 35 seconds.

My guess is it's caused by the excessive compression of the Mavic.

The jitter seems to happen about every 8 frames, although I haven't measured it.

This can be mitigated to some extent by making sure the shutter speed is quite slow, ideally 1/60th of a second or slower, which means using a neutral density filter. This will cause a slight motion blur which lowers the amount data that the compression algorithm has to deal with.

Also, if you're after getting the best quality, slow the movements down quite a bit compared to your example video. Apart from making the shot aesthetically better, this will feed less data to the compression algorithm so it doesn't have to work so hard.
2018-8-19
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PandaCheese
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Mike Warren Posted at 2018-8-19 19:16
I see the jitter through most of the video, although it's most prominent at around 14 seconds and 35 seconds.

My guess is it's caused by the excessive compression of the Mavic.

Thanks for the detailed analysis! So I guess it's expected then, instead of a defect.
2018-8-20
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DJKOR
Second Officer
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Australia
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If I was to take a guess, I would say shutter speed. The other day I wanted to take some video as I have not really taken much during the day since I switched to using manual mode for photos. Coming from mostly taking photos and not knowing much about videos, I used manual mode, set my ISO to 100 and compensated for the over-exposure by using a fast shutter speed instead of the usual 1/50 I would use when combined with 4K/24FPS as most of my filming lately has been near sunset/sunrise so never had to increase shutter speed... which from memory was higher than what yours would have been. I have since learnt this is why ND filters are important because shutter speed is not the answer to reduce exposure on my Mavic Air (as I lack a variable aperture). The end result is this (parts of it are sped up but it is still noticeable when not sped up):

2018-8-20
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