Documentation of vertical reference required for DEM

[S0sh0rt]

What is the vertical reference for the DEMs? Most DEMs are MSL, but the SAR computations require WGS84. Are you applying EGM 96 or 2008 to the DEM?

[alexamici]

This is entirely left to GDAL/Proj, if the metadata on the DEM files is correct and Proj handles the translation to geocent / ECEF, then you are fine.

You can see in the download script for the notebooks that I add the explicit vertical reference EPSG:5773 to the command line in the pre-process step, as the DEM uses EGM96 heights but doesn't declare it: gdalwarp -r bilinear -s_srs EPSG:4326+5773 ... Then GDAL converts the DEM to WGS84 ellipsoid heights and add correct metadata.

[alexamici]

@S0sh0rt but you are right, I need to document this. [I was quite sure I mentioned it in the README, but it's not in the there]