Hi there all.
This week, I have spent MANY hours collimating my 1150mm f4.5 Newtonian. I am using a video from The Astronomy Shed where you use a camera and Mire de Collimation to firstly perfectly centre the secondary in the draw tube and then align the primary.
I have done this to the best precision I can muster. But I still am getting odd star shapes and the diffraction spikes are tilted.
My question is this...
I am using my ASI120mm and the handy little fisheye lens that came with it. Would the fisheye lens be causing distortion in the image such that what I think is a perfect(ish) circle on the computer monitor is not?
Thanks for your help
Scott