DJI Mavic, Air and Mini Drones
Friendly, Helpful & Knowledgeable Community
Join Us Now

Lens vignette on M3M RGB camera

Joined
Jun 5, 2023
Messages
6
Reactions
1
Age
31
Location
Washington State
Just recently purchased a Mavic 3 Multispectral for work and flew my first test flights with it. I was disappointed to see a lens vignette on the RGB camera. I know this is a wider angle lens than the Mavic 2 Pro but is this normal?

I do a lot of mapping work and I'm concerned the corners could be an issue during stitching. Metashape has a setting for ignoring static pixels but my understanding is that is more for dust on the lens than entire regions to ignore. Hoping to not need to do some sort of batch crop on these.

P.S. In Pilot 2 you can set zoom to 1.1x prior to starting the survey and it removes the vignette, but this seems like an annoying step to need to remember each time.
 

Attachments

  • DJI_20230531173718_0031_D.JPG
    8 MB · Views: 17
  • DJI_20230531173720_0032_D.JPG
    7.8 MB · Views: 12
I think you'll find all lens' have some vignetting especially wide angle. With DJI, lens corrections are made automatically in the drone. If for some reason this correction is not happening, you can import into Lightroom and make an import preset to the right amount of vignetting and other corrections. From then on, Lightroom will recognize the camera and the corrections will be done every time you import.
You could also snag it with DJI and they'll make a future correction to their S/W.
 
Thanks for the feedback. I have never used Lightroom for survey imagery but others have brought it up to me before as well. Maybe it's time to look into that finally.

I was about to post on the DJI forums and came across this post, where someone mentions a "dewarp" setting in Pilot 2. This was easy enough to find in the camera settings and did in fact remove the vignette in the camera view.

Also tracked this down where someone recommends leaving dewarping off given that the camera profile will be accounted for in photogrammetry software, which I am familiar with being the case. I suppose I'm just used to the camera profile also being applied to the jpegs themselves which is what threw me off.

I'm still debating whether to leave dewarping off or not. The extra pixels could be marginally beneficial I suppose but turning dewarping on feels more like the user experience I'm used to. Curious if others have any opinions on that, thanks!
 
In any case, it is technically better and more accurate to leave the images in the native format - i.e. leave the lens correction switched off for technical flights (this is also the default). You have to keep in mind that the correction not only “uncurves” the image but also crops into the image. Technically, of course, this means a change in the content shown in the image. Completely different with aesthetic shots! Here you should of course switch on the automatic distortion compensation in order to get straight lines in the image and produce “correct” images for the viewer. So for technical shots off - and aesthetic shots on. The professional and relevant photogrammetry software can handle this well because it calculates the original images correctly and therefore the values are technically correct.
I hope I was able to shed some light into the darkness.
 
Thanks @a2k for your reply. I agree that the best approach is to leave dewarping off for photogrammetric surveys and turn it on for aesthetic manual shots. Kind of a pain to switch back and forth but this is what I'm doing going forward. Thanks!
 
  • Like
Reactions: a2k

DJI Drone Deals

New Threads

Members online

Forum statistics

Threads
130,597
Messages
1,554,232
Members
159,603
Latest member
refrigasketscanada