I have no idea if there is some kind of standard for this but the angle of the framing is backward compared to stellarium and the Asiair software. For example 45° in telescopius is equivalent to 315° in stellarium.
This topic is also discussed here: https://forum.telescopius.com/t/telescopius-showing-different-framing-than-stellarium/414/3 and I believe it’s also related to this: https://forum.telescopius.com/t/strange-rotation-angle-in-telescope-simulator/646
Hi @nico1038. Given the amount of questions I get regarding the PA, I’ve just posted this topic to try and clarify any confusion. I hope you find it useful 