Nexstar 8 se astigmatism help!????

Hello!

I have star tested a new Nexstar 8 SE and found a mild astigmatism when focusinf . I would like to know it it may caused for pinched corrector or any other reason. 

I also could not align the telrad red dot with the scope main optics.. Is it possible that the scope secondary is misaligned in such way that causef some astigmatism ? The collimation is only a little bit off also.

Thanks!!
Andre

Could be that you're seeing tube currents. These mimic astigmatism. Take a picture of the unfocused star image inside and outside of focus and post.

Rolando

It's possible that the diagonal is faulty, did you try it without the diagonal?

Jon