Hi all,
I have been trying to fine tune my PHD guided Skywatcher 200mm f4 Astrograph with baader mark III coma corrector to get round stars but I still have small fat tear drop stars in corners of image. My question is this the best I can expect from my Newtonian and the baader corrector or do I have to fine tune the distance of this lens to my DSLR Nikon D3 full frame sensor with spacers?
I have intentionally loaded a bigger image any help appreciated
regards Peter
http://digitalmacro.com/Files/lagoon1.jpg