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Hi All.
I wouldn't be surprised if it is a Bird/Jones design.
It appears that, no matter what adjustments I make to the Primary, the aberrations are still present. On this scope, there are no correcting lenses, as the Celestrons and Meades had in the linked post.
I took out the mirror, and gave it a good clean, ala Mike Salway's little document. The mirror is shmick, but the light tails are still there. Being Chinese, I would suggest a round mirror. In actual fact, I asked this exact question before buying it, but you can't get a straight answer out the sales staff there (in China).
I can play with the collimating screws till the cows come home at the moment, but the quality of the image does not change. And not having a Crayford focusser on the OTA means that getting super-fine focus just isn't going to happen with this scope.
Please note : I still have not properly collimated this scope, to this point in time. I don't have the personal budget to buy any collimating device, for a scope that is going to sit in the corner, if it doesn't work well.
It's not a huge problem, as I really did only buy this scope, to test out the quality. I think I have my answer now. Hat rack ...
Now for the next question ... how likely is it, that I will find a parabolic, F/9 6-inch primary mirror? I know Bintel sell F/5 and F/8, but the scope's specs (assuming they are actually correct) are f=1400mm, d=150mm. To me, this says F/9.333^.
Does the f=1400mm refer to the focal length of the mirror only, and can this be changed easily? Or does changing the F/Ratio (currently F/9) affect all of the other components?
Not a fan of a total rebuild of this unit just yet. Maybe once the next scope comes along.
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