|
Hello
I think I'm seeing the light at the end of the tunnel.
Last night I colimated again the scope from scratch.
I first completely backed the primary, then removed the secondary and adjusting only the focuser colimation ring I ensured that the HG lasser beam passed exactly through the center of the hole.
Then attached the secondary again, but put it flat, touching the spiders without fastening the colimation screws.
Inserted the concentric circles attachment and projected it to a flat surface.
The result was perfectly concentric circles.
Then loosened the central screw (3 turns as it was originally) and adjusted the secondary with the colimation screws until I obtained the same concentric circles.
After that I did a visual test to a bright star, getting a perfect circular defocus donut.
I then attached the lodestar and using CCDinsector did some minimal tweaks on the secondary until i got less than 1 arc second colimation error.
Then focused the star.
What I could see, is that I got difraction spikes from the secondary holder vanes, but also got spikes from the primary holder clips.
The combination of both gave me the sense of a triangular shape....
After that I did some tests on the omega centaury core getting reasonable round stars.
My next step is to remove the primary holder clips and do a test on brighter stars (or augmenting exposure times).
Regards
Geert
|