Does anyone know what the altitude is based on for the Mavic 2 Enterprise Advanced?
I have never really paid attention until I went to process a dataset in Pix4D and found the altitude that Pix4D pulls from the metadata does not match up to EGM96 geoid.

Looking at the 3 different altitudes in the metadata the Absolute Altitude field which Pix4D uses and also is the altitude that Windows shows in the Details section under Properties is not correct. The Relative Altitude in the metadata makes sense for the flight. But the altitude being reported as height above ellipsoid would also be close.

Does anyone know this answer?

Thanks!

This question has been asked many times over the years. The simple answer is that the aircraft derive their altitude from a simple barometer chip, and it shows the altitude with respect to the take-off point of the aircraft. As to the other figures, I will leave it to Labroides to answer that. Hopefully he will be along shortly.

Thank you for your response, and I was aware of the barometer being used for altitude. I was just wondering as the Phantom 4 RTK bases its altitudes off of height above ellipsoid and I was wondering if maybe this drone does the same since it is RTK capable at least for positioning.

Right now myself and Pix4D Support are trying to figure it out as my altitudes do not come close to being based on EGM96, and this is for all of my images over the last year, not just one dataset.

It's a bit complicated to explain on my phone.
But if you can post one of your jpg images, I can show you the two different heights in the metadata and explain them when I get home.

I have all three altitudes, Absolute, Relative and GPS (Which is not based on GPS).
Pix4D Support has an idea that maybe this drone is reporting the elevations obtained from the barometer as compared to height over ellipsoid and not compared to EGM96. This is not my theory as I found the Relative Altitude to be actually spot on, but Pix4D is using the Absolute Altitude.

Link to M2EA Images
https://drive.google.com/drive/f ... iC5zs_2?usp=sharing

In the Folder DJI (1) is what I am referring to right below.

Absolute Altitude  28.17 m
GPS Altitude Ref Above Sea Level
GPS Altitude 28.1 m AMSL
Relative Altitude 53.85 m

The flight was conducted at 177 feet AGL or 54 meters AGL
Pix4D is using 28.1 m or 92 feet AGL
My orthomap output is shifted into the -40 m range.

I am writing a study in the use case for Low Cost Public Safety sUAS when used for out of the box vs GNSS PPK/RTK and/or GCP enhanced maps. My out of the box example with the Mavic 2 Enterprise Advanced is so wildly inaccurate it causes a bit of confusion for those reading. When adding GCPs it tightens up very nicely though as it should.

I have opened a case with DJI to get their thoughts. I am just wondering that this sUAS may use height over ellipsoid like the Phantom 4 RTK since you can add an RTK module (I know it does not tag the images).

I do thank you for your responses and I am hoping that someone may know if the ellipsoid theory is correct. But I really do not think it is as almost all consumer drones report altitude as compared to EGM96.