On Nov 2, 2015 6:34 PM, "Felix Ruess" ***@***.*** wrote: Exif doesn't allow negative alt? Also the alt written to exif seems to be the ellipsoid alt and not geoid (MSL)... Alt above mean sea level would probably make more sense here... — Reply to this email directly or view it on GitHub 70e4b94#commitcomment-14133551 .