Attempted viewing of Saturn

[DomDubois]

This morning I woke up early, bound and determined to view Saturn and Mars for the first time.  Despite the massive clouds moving in to spoil my viewing, I could see the planets shining brightly, and had some time with clear skies before the clouds would move in.  I set up my telescope, which is a 10" dobsonian (apertura), and collimated it quickly.  I should note that I set the telescope up inside, and viewed through the large glass window on the sliding doors to my back deck. I put in a 9mm plossl eyepiece that came with the telescope, which I've enjoyed many views of Jupiter and the moon with.  

By now, the clouds had covered Mars, so I pointed the dob towards Saturn, sat down and started focusing.  I tried and tried, but I just couldn't get the planet to come into focus... I could see its rings and make out the planet sitting inside it's rings, however it wouldn't focus as crisp as I've viewed Jupiter.  So I guess my question here is, why?  Was it because I was viewing through my glass door? (It was clean! haha) or perhaps even though it looked clear out (in that part of the sky) the viewing just wasn't any good?  

I'm very new to this hobby, so I'm having trouble differentiating between was it me or the conditions?

I should note, when I first got the telescope, I regrettably took it outside on a 15 degree (F) night, and it developed frost on the primary mirror, I took it inside and the next time I took the telescope out,  could see what looked like water spots on the primary. Everything I've read says don't clean the mirror, but could this have contributed to the focusing issue?

**the frost issue is why I now view inside, through the glass door.

[brantuk]

It's just impossible observing through a window - you'll never get a good focus and most of the time the image will be distorted in some way. You really need to be outside with it. A frost won't hurt the scope but if you pop a fan on the back of the primary to keep air moving over it's surface then it should stay clear. The scope needs to cool down and be free of warm air currents - this can take half an hour to an hour before observing.

You really aren't giving yourself much chance at all using it indoors. Saturn is low at the moment and difficult enough to see as it is through all the turbulent atmosphere - which gets thicker the lower you go towards the horizon. So you need to get some warm clothes, boots, gloves, etc and brave the outside I'm afraid.

You can clean the mirror - but it rarely needs doing unless there's a considerable build up of dust. When it does need doing use only luke warm water with a few drops of pure soap, distilled water, and isopropyl alcohol. Look for Steve Richards mirror cleaning guide on "Youtube". Hope that helps

[Peter Drew]

Hello DomduBois.

Welcome to this forum. The good news is that there is nothing wrong with you or your telescope. The poor Saturn image will be due to the combination of Saturn's low altitude and looking through the glass door. No matter how clean the glass is it will not be of astronomical quality and will degrade the image. The water spots will have little effect on the performance of the mirror and cleaning will best be left until the mirror really needs it. 

[DomDubois]

Thanks for the responses! Very helpful as I mentioned earlier I had an idea of what was going on but I wasn't sure about it.

I love viewing outside despite the cold, but my wife doesn't, haha. So I started setting up inside because I was more concerned about the frost on the primary. I plugged in the fan and let the telescope adjust to the temperature for about an hour and a half, but the cold temperature drained the batteries of the fan and the frost developed anyway   

I did enjoy a decent view of M42 and M41 through the glass window, so I thought perhaps I could get away with viewing saturn this way.  I suppose I'll have to be a bit more patient with my viewing, it's hard being new and wanting to view so much, but the weather here has been very cloudy so any small window (of time) that I get to view I've been trying to take advantage of.

[Langy]

As said you can't really observer through glass. Even with the door or window open you may still have problems with the disturbance of the warm air from the house compared the cold air outside.