Star testing an 8" Konus reflector

Hello everyone. I have a question about star testing. I know from reading that one way to tell if your optics are perfectly collimated, and in good condition, is if you get perfect concentric rings when performing a star test. The last several nights I have had my Konus 1793 200mm reflector out, my star tests have been a bit dissapointing. No matter how I focus, the perfect concentric rings I'm supposed to see just don't appear. What I do get are points of light that appear to have frayed out edges, resembling something like a snow-flake of sorts.

I have collimated my scope with a laser collimater, and according to several different websites and instructional texts, appears to be properly collimated. The nights that I went observing also "appeared" to be clear and of good seeing. Since I am new to the hobby though, I am not sure if there could have been atmospheric turbulence.

My views of the moon on the other hand is very sharp and detailed, and Jupiter and it's moon looks pretty good. I have been able to see 4 or 5 moons, and Jupiter itself shows two or three bands. The color is a bit dull though.

Could anyone give me some advise on this matter?

Thanks in advance for all of your help. I have found these forums and its patrons to be invaluable.

Regards and clear skies,

James

James,
I agree with Jeff. It seems like you have astigmatism from an overly tightened mirror clip. I am not sure of the means by which your mirror is held in the cell but make sure the clips or retainers or screws do not impinge upon the mirror. Lining the mirror clips with cork sheeting will prevent the problem of the mirror shifting around if you are concerned about excessive play between the mirror and it's retainer.