Quote:
Originally Posted by AstralTraveller
Start by checking collimation. Look at some stars out of focus. You should see a central disk and probably an outer ring. They should be round and symmetrical. If not look up how to collimate a newtonian. There are plenty of sites.
However, to me it sounds like a seeing problem. Either the atmosphere was very poor and/or Saturn was low in the sky and/or the scope wasn't properly cooled. Oh, and is your eyepiece clean? Just because it's new doesn't mean it's pristine.
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Hi, thanks for your reply. I originally collimated with a cheshire. I watched a bunch of youtube videos and I was pretty confident. But I bought an orion laser collimator a couple of days ago and adjusted the primary slightly. I bought the laser so I could check the primary mirror when outside in the dark after the tube had cooled. When going outside, I have to sit the ota on a chair, carry the base outside, then carry to ota to it. So perhaps the primary might shift slightly in the transfer. I'll try the laser outside tonight. On the star test, I definitely get what look like good concentric circles, the only difference being the circles don't look like solid lines. It's more like a circle of close dots when defocused. Does that sound right. When you say it sounds like seeing conditions, how clear should Saturn be? And how big in the ep of a 9mm GSO plossl. I'm just trying to get an idea of what to expect. Thanks again.