Geotag with RTK

Hi Everyone,

As far as I’m concerned geo tagging is not easy regarding to altitude when geo tagging with RTK. In order to get the right amsl altitude you need to check “Use GPSAlt”. Once you have geo tagged the images, these will have the amsl on the ground at take off plus the relative altitude you made the survey. For example, if we were at 10m amsl and did survey at 30m relative, the result of geo tagging is 40m. Now, the question is, if there is anyway to subtract the relative altitude from the GPS altitude and so, have the right amsl altitude which is 40m - 30m = 10m. For this reason I thought that “Rel Alt Base” would do the trick, but it does nothing. What is Rel Alt Base for?

Thanks in advance.