Collimating issue

[Joaquarossi]

Hello all, 

I’m relatively new to astronomy and wanted some advice. 
 

ive recently bought a Meade 10 inch lx200. 
when trying to collimate I defocus a star and instead of finding a round donut shape It is a donut with one flat side. The only thing that moves this flat side is moving the off axis eye piece. Is there an issue with the eye piece or am I missing something? 
I can see the secondary mirror shadow and adjusting the collimating screws does move the shadow but does not affect the flat side of the donut. 
 

what am I missing? 
 

thanks in advance. 

[Spile]

You’ve defocussed too far. The star test is fine for checking the primary is aligned but totally impractical for using as a reference when adjusting the mirror. A cap or a Cheshire eyepiece and sight tube combination tool is my recommended tool.

https://astro.catshill.com/collimation-guide/

Edited December 8, 2021 by Spile