Hi guys,
Hope you are all well and getting clear skies during these tough times. I have a GSO 830 10" F5 reflector with a Moonlite focuser. For collimating I use the Howie Glatter laser collimator. The collimation process I use is as follows:
I attach the barlow adapter to the howie glatter and put it into the focuser, it projects a tight red dot onto the primary mirror. After adjusting the screws on the secondary to put the dot perfectly centered in the dot on the mirror, I take the howie glatter out, remove the barlow and put it into the "tublug" (
https://www.collimator.com/barlowedc...ion/125-tublug) so I can adjust the primary mirror.
All looks great for both primary and secondary mirrors with the laser dot remaining perfectly on the primary dot and shining perfectly through the tublug, I unlock the RA clutch and rotate the counterweight bar to be horizontal.. the red laser dot then moves onto the edge of the alignment dot. If I rotate it 180 degrees the opposite way so the counterweights are facing east, it isn't *as* bad...
My question is, what could be causing this movement when I rotate? I have a Farpoint Dovetail Universal Plate for the main mounting to my NEQ6 Pro, then the 2 rings that come with the GSO830, then on top the standard dovetail that came with the GSO830 to stiffen it all up. I've tried tightening my primary mirror cap screws that secure it in, made sure my adjustment knobs are all tight, checked all my bolts on the dovetail.. I'm at a loss? Has anyone else managed to sort out collimation getting out of whack when rotating the scope?
Sorry for the long post, but I just don't know what else I can do because it is affecting my DSO images (stars are becoming lines or commas)
I have uploaded a video I took on my phone whilst trying to hold it against the scope and looking at the dot.. excuse the shakyness of it but you can see the laser dot moving as I rotate it about the RA axis -
https://www.youtube.com/watch?v=zsDg9fet9cc
Cheers, Mike