Phantom 4 Pro v1 mapping problems with camera calibration

[vgo195]

Hi,
I got a used P4Pro v1 after crashing my P4 advanced.
With P4 Adv I was very happy with the mapping results. I always use 5+ GCP's and the alignment with Metashape was always within 2-3 cm on 40-60m altitude missions.
With the new (used) drone P4Pro most projects have problems with the gcp's. I have incostintent results mosty in elevations like 30cm off the check points.
I know I am not doing something wrong because I use also other P4pro's that don't have this problem.
Is the camera bad? Is the focus problematic? It seems that Metashape can't calculate the camera calibration correctly.
Any thoughts?
I did a firmware refresh and will test it soon. Will it help or is it irrelevant?

 

[CR125Honda]

Following as I'm curious what your fix is going to be.. Just thinking out loud, there's not an ND filter on the new drones lens is there? Don't know if that would effect it anyway, just a thought.

 

[vgo195]

No there is no ND filter. Just the original clear filter.
With double grid missions the problem is reduced but it shouldn't occur even on single grid missions with 80/80 overlap.
Did some tests with camera settings and the best quality based on Metashape estimation is with f4-5.6. I always use shutter speed 1/1000-1/1600 to reduce motion blur.
I will do some more tests and report back.