Hi All,
I have an NEQ6 mount on which I use an Skywatcher ED120 piggybacked by an Orion ST80 guided by PHD Guiding and have had pleasing success for the last year.
I now have a C11 on the mount piggybacked by the ST80 and I'm getting oval stars around either side of zenith, but if I continue tracking toward the horizon the stars resume their sharp round shape.
Since it has guided perfectly from all parts of the sky with the ED120, are the oval stars a side affect of the extra weight of the C11 when the RA axis is parallel to the ground or could it be some other factor?
Hope someone can work their magic for me?
Thanks in advance.
Mook