Image quality issue [sample]
1174 6 2017-4-2
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fansd6613042
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Germany
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Hi,

I got my Mavic ~ 2 weeks ago. So far I am loving it for a flying device. Sadly I am suffering from the video loss issue discussed in another thread as well. Howeever, my main concern is the camera quality. It is bad to a degree that I think I might have gotten a faulty camera. So I want to ask a couple of other pilots if this is the quality you are experiencing as well.

A lot of people suggest flying in D-Log and the videos they post look very great, so I am really not sure what I might be doing wrong, if anything. The following two samples are shot in 4k 30fps with D-Log and the other options all set to 0. Focus and shutter configuration was set to auto in the second sample, the first sample was using a fixed shutter speed. What you can clearly see in the videos is that the compression is so bad that the artifacts in the trees in the background are jumping from one keyframe to another. Also if I now color grade this by increasing saturation, darkening the darks and brightening the lights, the color range get so much stretched that you can basically see the brightness jumping from one level to the next (sample 3).

Sample 1 - D-Log 4K 30fps manual shutter
Sample 2 - D-Log 4K 30fps auto
Sample 1 - Graded 4K 30fps - Look at the clouds that shine through the trees
Sample 2 - Graded 4K 30fps - Look at the tree branches in the background

(Note that in all samples focus was set correctly. At least according to the peak threshold option, the center of the image was in focus and with it the trees in a similar distance. So for Sample 1 this means the foreground was focussed, in Sample 2 the trees at the distance of the tree on the left were in focus.)

Is anybody else having these issues?

Michael
2017-4-2
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4wd
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Flight distance : 545817 ft
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United Kingdom
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The ungraded looks prety much as I'd expect especially the auto exposure.
Beware of under-exposing, best results are always going to be in good light.
2017-4-3
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fansd6613042
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Thanks @4wd for the answer. You said the ungraded looks like you expect it. So you think the issues that are seen on the graded one is due to bad grading? I am not sure what I did wrong there. I use DaVinci Resolve and applied the LUTs from DJI that convert the Mavic's D-Log to Rec709 and then only did some minor tweaks. So I am not sure what I could do differently there.
2017-4-3
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KaiM
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Flight distance : 456877 ft
Germany
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fansd6613042 Posted at 2017-4-3 06:43
Thanks @4wd for the answer. You said the ungraded looks like you expect it. So you think the issues that are seen on the graded one is due to bad grading? I am not sure what I did wrong there. I use DaVinci Resolve and applied the LUTs from DJI that convert the Mavic's D-Log to Rec709 and then only did some minor tweaks. So I am not sure what I could do differently there.

As far as I know, DJI deleted the old LUT from the website and the old LUT is not suitable for the new firmware.
You can find a free LUT for the Mavic (with new firmware) here: http://www.groundcontrolcolor.com/mavic.html
2017-4-3
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Flybee
Second Officer
Flight distance : 2203983 ft
Sweden
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I think the sample 1 graded or not have other "problems" and that is that you are measuring the light from the threes as you are rising and then it take some time before exposure adjusts, so it's hard to say cause the sequence should have been longer.

What White balance did you have?

I use art +1 0 0 and it have never failed try that one and see if there is a difference (requires IoS) device.
See here what I mean. 30 secs in and in the end like 2 mins approax, see the difference in the clouds. Then you give the camera time to adjust. As you can see threes are really hard to capture.



Good luck
2017-4-3
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mildim
lvl.2
Flight distance : 981558 ft
Switzerland
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Flybee Posted at 2017-4-3 11:25
I think the sample 1 graded or not have other "problems" and that is that you are measuring the light from the threes as you are rising and then it take some time before exposure adjusts, so it's hard to say cause the sequence should have been longer.

What White balance did you have?

Always nice to see Munich
2017-4-3
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fansd6613042
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Germany
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Flybee Posted at 2017-4-3 11:25
I think the sample 1 graded or not have other "problems" and that is that you are measuring the light from the threes as you are rising and then it take some time before exposure adjusts, so it's hard to say cause the sequence should have been longer.

What White balance did you have?

Thanks for your reply. That video looks in deed very similar to what I got out of the Mavic. You can see it in your video e.g. in some of the reflexions right at 0:45, when looking at the black roof / tent. The reflexions are not smooth, they jump from being there to being gone.

It seems to be normal for the Mavic then, it's just still very frustrating that my old GoPro has a crisper image quality than what is mounted below the Mavic. It can only do 1080p, but at least there everything is cristal clear and very sharp. No compression artifacts.

I'll try shooting in 1080p or 2.7k and see if this has the same compression issues. The Mavic is a fantastic flight device, but I am really struggling to enjoy the camera.
2017-4-4
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