# Settings for Mosaic using Telescopius and ASIAIR + **URL:** https://forum.telescopius.com/t/settings-for-mosaic-using-telescopius-and-asiair/611 **Category:** General Questions **Tags:** mosaics **Created:** [October 12, 2022, 4:54am UTC](https://forum.telescopius.com/t/settings-for-mosaic-using-telescopius-and-asiair/611 "2022-10-12T04:54:42Z") **Posts on this page:** 1 **Showing post:** 2
### Author: ![sebagr](https://forum.telescopius.com/user_avatar/forum.telescopius.com/sebagr/32/6_2.png) [@sebagr](https://forum.telescopius.com/u/sebagr) #### Post date: [April 28, 2023, 7:59pm UTC](https://forum.telescopius.com/t/settings-for-mosaic-using-telescopius-and-asiair/611/2 "2023-04-28T19:59:24Z")
Sorry for the late reply! There is a standard by the International Astronomical Union, by which the Position Angle is measured East of North in the celestial sky (noting that East in the Sky is West on the Earth). Here you have a topic I wrote explaining the Position Angle issues. > [@Position Angle / Rotation Angle - Is it backwards?](https://forum.telescopius.com/t/position-angle-rotation-angle-is-it-backwards/757): > > There is a convention for measuring angles on the sky, and it’s called Position Angle. Quoting the [Position Angle article](https://en.wikipedia.org/wiki/Position_angle) from Wikipedia (bold is mine): “In astronomy, position angle (usually abbreviated PA) is the convention for measuring angles on the sky. The International Astronomical Union defines it as the angle measured relative to the north celestial pole (NCP), turning positive into the direction of the right ascension. In the standard (non-flipped) images, this is a counterclockwise m… As per ASIAIR Plus, I’m not sure how they handle it but I do know there are many great astronomy software that measures the rotation angle West of North instead of East of North. Maybe that’s the issue here, but you’ll have to check with them. Any updates/confirmations on this by any ASIAIR Plus user would be awesome to help other users 🙂 --- _[View the full topic](https://forum.telescopius.com/t/settings-for-mosaic-using-telescopius-and-asiair/611)._