Panorama Stitching Isn't Accurate
2952 18 2018-2-25
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NFG
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Australia
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Does anyone else have this issue with the panorama stitching?  The edges of the individual images overlap, and there's a double-image on every seam.  I'm not sure if I should just accept this, or if it's not working right.  

seam.jpg
2018-2-25
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Wachtberger
First Officer
Flight distance : 261509 ft
Germany
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This is not normal at all. Was it very windy? Do you get this on each Pano?
2018-2-25
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AM0
lvl.4
Flight distance : 415554 ft
Estonia
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Most of the panoramas I have taken have similar blurry areas in the stiching zone.
For comparision I stiched one panorama from the raw images with lightroom and got much better result -- no visible errors.
It seems to be a problem of onboard stitching, not the capture.
2018-2-25
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Wachtberger
First Officer
Flight distance : 261509 ft
Germany
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It does not happen on mine.
2018-2-25
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NFG
lvl.2
Australia
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This is not normal at all. Was it very windy? Do you get this on each Pano?

Yup, every one tried so far.  Doesn't seem to matter if it's windy or not.  

...I stiched one panorama from the raw images with lightroom and got much better result...

Yeah, that's my next step, I guess.  I was hoping to avoid it, I'm actually quite lazy.  ;)
2018-2-25
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Tadango
lvl.4
Flight distance : 232359 ft
Netherlands
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I see a little blur / ghosting in some of the seems, but it is very little.
2018-2-25
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NFG
lvl.2
Australia
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Looking more closely at that image, the horizon is lower on the right side, but the curb on the street nearer to the Mavic Air is higher on the right side.  That seems to me to be a more critical misalignment.  =/
2018-2-25
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spookster
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Germany
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Probably got hit by wind gust during shooting the pictures and slightly changed attitude. You didn't get strong wind warning during that flight?
2018-2-25
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NFG
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Australia
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spookster Posted at 2018-2-25 05:32
Probably got hit by wind gust during shooting the pictures and slightly changed attitude. You didn't get strong wind warning during that flight?

In every seam, in every image taken?  That's one hell of a good gust.  =(
2018-2-25
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AM0
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Estonia
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Here are some examples. Crops from the seam areas of different Mavic Air panos, taken on different days.
I can understand if the branches are moving, but houses?

2018-2-25
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AM0
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Estonia
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And here is the third example. This time I had raw files so I assembled the same pano from these with  Lighroom.
This is what Air made. Note that there is a stripe even in the sky.


And here is the similar crop from the Lightroom version:


They are a bit different in size and color, but as they are just a tests, I din't bother to be scientific ;-)

BTW it was a gusty day, so Air had to work hard to keep things stable. Judging by LR result it didi it pretty well :-)
2018-2-25
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spookster
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Germany
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I've had similar results on Spark resulting from wind. Just saying.
2018-2-25
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NFG
lvl.2
Australia
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I don't think there's any real possibility that it's a simple wind problem when manually stitching the photos can produce better results.  

It sounds to me like the stitching algorithm in the Air needs a bit of refinement.  I'm not yet ruling out a misaligned camera on my unit, and I think it's pretty obvious that wind can play a part (I mean, of course it can).  But the difference in alignment on my own images would suggest a consistent movement in all directions, or a wind that spins the drone, which - if it's happening - is far too subtle for me to notice.  

But, to reiterate my tentative conclusion, if the images CAN be aligned and the Air DOESN'T align them, then the problem is in the software.
2018-2-25
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Landbo
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Flight distance : 502792 ft
Denmark
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I suppose the biggest problem with composing the displayed images is due to a poor contrast in the pictures where it goes wrong.

Regards Leif.
2018-2-25
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NFG
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Australia
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Landbo Posted at 2018-2-25 16:07
I suppose the biggest problem with composing the displayed images is due to a poor contrast in the pictures where it goes wrong.

Regards Leif.

How do you reach that conclusion?

In the examples shown, there's a black leaf-less tree against a grey/white sky, or pale buildings and snow and black windows.  That's about as high-contrast as it gets.   

Granted, in my example there's a little less, but...  I don't see that a lack of contrast could possibly be the problem.
2018-2-25
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QuadKid
Second Officer
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United States
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NFG Posted at 2018-2-25 16:13
How do you reach that conclusion?

In the examples shown, there's a black leaf-less tree against a grey/white sky, or pale buildings and snow and black windows.  That's about as high-contrast as it gets.   

I don't use DJI's software to create Pano's (360° or 180°) a good free image stitcher is MS ICE you can get it HERE and it's free. Windows or Mac. I always save my Pano images (Shot in RAW Format) to a folder on my PC, then extrapolate them into Photoshop to do color correction , export as a .DNG, then stitch them using MS ICE and save as a JPEG.
2018-2-25
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Landbo
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Denmark
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NFG Posted at 2018-2-25 16:13
How do you reach that conclusion?

In the examples shown, there's a black leaf-less tree against a grey/white sky, or pale buildings and snow and black windows.  That's about as high-contrast as it gets.   

I do this by looking at the result of your stitching. I've had the same problems so many times that I can see that the green leaf you have in the middle of the picture is most likely not to succeed. Try and take some sharp images with good contrast, as well as  a simple object and put them together, then just see.

Regards Leif.
2018-2-25
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Landbo
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Denmark
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QuadKid Posted at 2018-2-25 16:30
I don't use DJI's software to create Pano's (360° or 180°) a good free image stitcher is MS ICE you can get it HERE and it's free. Windows or Mac. I always save my Pano images (Shot in RAW Format) to a folder on my PC, then extrapolate them into Photoshop to do color correction , export as a .DNG, then stitch them using MS ICE and save as a JPEG.

Yes, MS ICE is one of the best stitching programs on the market and it's free.   

Regards Leif.
2018-2-25
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AM0
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Flight distance : 415554 ft
Estonia
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Mavic Air has a limited processing power and probably simplified stitching algorithms to be able to fly and make panoramas at the same time.
I hope they can refine these further to get better results out of the little wonder, so that the onboard panoramas can be at least shared on the web.
I am sure it will never be equal to specialized software on a powerful desktop computer.
So for best results I will always keep the "Save unstitched panorama images" option checked :-)
2018-2-27
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