Hello everyone!
I've been have some issues lately with Agisoft and DJI drones.
It seems like all of the DJI drones has another altitude in the EXIF data than the ones that I want to use.

The ground has been surveyed with a Leica RTK GNSS, and I have obtained altitudes of 29-32m.
The drone flight was done 60m above ground, so I'd assume around 90m in elevation for the drone.

The images have an altitude of 127m, I assumed this was an issue with non-RTK drones, but here, flying a RTK drone I had hoped for correct RTK elevations in the image EXIF.
I have tried converting from WGS84 to other reference systems in Metashape, but altitude remains unchanged. Is there anything that I am missing?

/T

You have to implement the geoid. DJI drone altitude are WGS84.
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LV_Forestry Posted at 10-23 23:50
You have to implement the geoid. DJI drone altitude are WGS84.
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Do you know a nice way to do that in Agisoft?

I'd assume that these vertical datum transformations were already included when transforming the data in process?



As seen on the image above I'm using EPSG 4326, where the correct ellipsoid is chosen, and I am transforming to EPSG 3006 where the vertical datum I am aiming for is also chosen.

TangoMango Posted at 10-24 00:11
Do you know a nice way to do that in Agisoft?

I'd assume that these vertical datum transformations were already included when transforming the data in process?

You mix horizontal and vertical Datum. 3006 is a horizontal datum. SWEREF99 TM
https://epsg.io/3006

Then you must choose a geoid that corresponds to the system requested by your client. RH70, RH2000...
https://epsg.io/5718
https://epsg.io/5613


When you have the geoid you create a custom transformation in Metashape with the horizontal 3006 and the vertical one you choose.

TangoMango Posted at 10-24 00:11
Do you know a nice way to do that in Agisoft?

I'd assume that these vertical datum transformations were already included when transforming the data in process?

Beräkna geoidhöjd | Lantmäteriet (lantmateriet.se)
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LV_Forestry Posted at 10-24 00:26
Beräkna geoidhöjd | Lantmäteriet (lantmateriet.se)
Svenska geoidmodeller | Lantmäteriet (lantmateriet.se)

That might actually have helped me figure it out.

Thank you so much for your expertise and advice, greatly appreciated :-)