Height above Ground

[Cactus26]

Now that I am able to determine the coordinates for most of the photos using my photo application, I want to focus on the altitude. There are good ways to determine heights via DEM using the Lat/Lon.

First of all, I would like to try to use the correct terms: https://www.geographyrealm.com/what-is-the-difference-between-elevation-and-altitude/

The EXIF specification for GPSAltitude/GPSAltitudeRef suggests that this should be a "True Altitude" (https://www.awaresystems.be/imaging/tiff/tifftags/privateifd/gps/gpsaltituderef.html)

If you want to determine the altitude correctly using DEM, for aerial photos it would be be important to know the "height above ground" (i.e. "Absolute Altitude").

Is there a suitable tag for this?

Interestingly, there is WaterDepth, which could be misused for this.

Cactus

[Phil Harvey]

Hi Cactus,

Height above ground is not something that GPS measures, so you won't find a tag like this in the GPS realm.

Drones seem to call height above ground "Elevation".  In XMP, the DarwinCore seems to have some tags which may be suitable.

- Phil