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Old 29-12-2018, 09:06 AM
Greggles (Gregory)
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Greggles is offline
 
Join Date: Aug 2017
Location: Sydney, Australia
Posts: 75
Quote:
Originally Posted by gaseous View Post
I find those laser collimators are harder to align than the scope itself. There are several threads on collimating in the bowels of the archives. The softness of the stars at higher powers suggests poor seeing and/or insufficiently cooled mirror, but that's not to say the collimation may not be out also. A quick test is to gradually defocus a bright star at med-high magnification. You should get the shadow of your secondary mirror presenting as a dark circle surrounded by the light airy disk of the defocused star - if they are concentric, then you're on the right track. If the secondary shadow is not centred, then your collimation is out. Others will be able to explain this much better than I can.
Thanks for the response. Yeah this is why I shouldnt be writing posts at almost midnight. I was meant to mention star testing as you have reminded me. When I defocus a bright star at high magnification the mirror seems to be pretty dead center. But all the photos online show multiple perfect concentric rings around the mirrors shadow. I dont get that on mine it looks more like A bubbling ball of gas :p
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