Does anybody know what the azimuth convention in the https://cgit.kde.org/kstars.git/tree/kstars/skyobjects/skypoint.h and associated conversion routines is? Is this N=0, E=90 or N=0, W=90 or S=0, E=90 or S=0, W=90 ? I cannot find such a documentation in the source code. R. J. Mathar