I have spend a bit of effort trying to figure out what the geographic projection is of coordinates attached to the exif files of the photos taken on the DJI Phantom 3 advance. I assumed that it was in WGS84 with the elevation in its associated datum, but when I looked closely at the elevation values, there was a systematic offset that was closer to the NAVD88 datum (but still off).
I called DJI's tech support and was put on hold for a while, and they reported back that the it was indeed NAVD88. I am not sure I buy this answer though. The person I was talking to had no idea at first, and I had planted the term navd88 when I posed the question, and even spelled it out for him; I asked if the z was in a global ellipsoid or a local datum like navd88.
Like I said, I was on hold for a long time, so it is possible this is really the correct answer, but when I think about it, it doesn't make sense. These are flown all over the world, so why would you want a North American datum if you are flying in Tasmania for example. I suppose it is possible there is a list of local datums onboard, and it automatically applies it depending on the location, but I kind of doubt it.
I know that the onboard GPS in not very accurate, especially in the Z direction, but where I am at there is more than 13 meters difference between the WGS84 global ellipsoid and NAVD88. Knowing the datum will help strengthen my photogrammetry product.
I also went through all the DJI documentation I could find on the subject, to no avail.
Has anyone else examined this issue in detail?
Thanks!