Re: AStroart 7 photometry & Astrometry question
Posted: 11 Dec 2019, 18:50
It depends on the catalog: if the star was extremely saturated on the original plate or image then the accuracy on the position cannot be good. This is why some catalogs do not contain bright stars at all. For astrometry I wouldn't use any reference star brighter than 9.0 mag (by the way, in the Astrometry Window, the rejection based on O-Cs will probably exclude the star automatically).