Large kicks on GCPs

PIX4Dmapper PIX4Dmapper Questions/Troubleshooting
1

Hi, please can someone point me in the right direction?
I have been mapping with the Ebee/Pix4D combination for many years now without major issues. However recently we have acquired a Mavic Pro 1, for mapping smaller areas and calculating stockpile volumes. I have followed the usual steps in putting down an array of GCPs, well-spaced etc. However, I am receiving large errors on camera optimization and georeferencing. See image below.

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The GCPs have been surveyed using static GPS, and I am super confident in their accuracy. The images are clear and the markers are easily identifiable in the images. I have 11 GCPs and are visible in multiple images (ranging from 5 - 20).

When I imported the images, the camera model was automatically selected - FC220_4.7_4000x3000 (RGB). Is this the correct camera for the Mavic Pro1? Has anyone else experienced this?

regards
Dave

2

Hi David,

The FC220_4.7_4000x3000 camera model is the one corresponding with DJI Mavic Pro 1 camera. We noticed that Mavic cameras are highly affected by the linear rolling shutter and this can cause issues in the camera optimization and also reflects in the GCPs accuracies.

Cameras with the rolling shutter can be an issue for the reconstruction depending on the flight conditions and the area that is mapped. To mitigate the effect, we suggest applying a specific algorithm especially for flights with a regular pattern (lines).

Next time you fly with this camera, we recommend flying slower and/or higher to reduce the amount of linear rolling shutter distortion that is present in your images.

Let me know if applying the linear shutter optimization improved the results.

Best,