Hello,
I'm at my wit's end. I've been trying to get my secondary mirror adjusted on my Skywatcher 200p Dob. But i can't seem to get it central in the Cheshire once it's been aligned with the doughnut on the Primary mirror. I can get the secondary mirror nice and central in the Cheshire before I try and line it up with the primary doughnut. But once i start adjusting the three allen screws on the secondary, to get the doughnut in the centre, the secondary mirror always seems to move upwards and is no longer central in the Cheshire. I can't keep the secondary in the centre of the Cheshire AND get the doughnut in the centre as well. As far as I am aware everything should be central at the end of the collimation.
In the end I just used the collimation cap last night to do the secondary alignment and the result is in the photos below.
I took the telescope out last night and tried the Star Test and it all looked really good, all the circles were concentric. The moon also all looked really clear and in focus and I even found Orion's nebula.
I have attached photos of the view through a Collimation cap and the Cheshire.
My question is, do I keep on trying to adjust it to get it spot on in the Cheshire? Or does it all look and sound good enough as it is? As this collimation is starting to take all the joy out of owning a telescope 😞
Many Thanks for any suggestions.