Hi, I am new to flying the M300RTK and came across a few anomilies I was unable to resolve...if anyone has any insight I would be most grateful.

Using only the DJI Pilot app on the smart controller and the D-RTK base station I was only "allowed" to set a flight altitude of 40ft as the minimum, using the Zenmuse P1 sensor this gives roughly a 0.15cm GSD for an ortho mission. A project I am working on is wanting to fly at only 25ft to attain 0.10cm GSD. Is there a reason I cannot change this value below 40ft? The same question exists in terrain follow mode as it seems restricted to 82.1ft, is there a reason for this or something I am missing to change this value?

On the terrain follow mode I have another question, after uploading a Digital Surface Model and loading it into the mission plan all seemed to make sense, the aircraft was going to fly 82.1ft above the DSM derived data, the mission altitude display showed that it would fly DSM+82.1ft, however, on launching the mission the M300 flew 130ft higher than was anticipated, but followed the terrain as expected, so at DSM+212.1ft.

I have been reading about ellipsoidal height vs gps derived but 130ft seems excessive in my mind but it is not a strong subject for me yet.

Any suggestions??

Many thanks.

To start with, check which coordinate system your DSM has. Most important, what is the refernce surface for the Z-axes.

Is there any update to the terrain following? I work for a geospatial firm and confirmed the correct geoid vs ellipsoid of what I'm trying to import, but there are still issues. If I follow the DSM on the smart controller, the drone wants to fly ~100ft above the planned "Terrain Follow Height". What's interesting is that if I turn terrain follow off, the flight lines change minimally. When executing the non-terrain following flight, the planned overlap and GSD are accurate to what is actually collected (tested and proven), which means when I do execute the terrain-follow mode enabled, the dataset has a lower resolution and less overlap than what was planned (tested and confirmed - because it's obviously flying too high). Essentially, when following terrain, the drone wants to fly higher than it should, but then doesn't account for appropriate GSD or overlap.