Winter viewing, bad for my telescope?

This is my first year stargazing. I have a 6" dob and i've noticed the few times i've taken it out this winter that after being outside for a while and then coming back in the house I have a fine mist or a kind of condensation on my scope. I'm mainly conserned about my primary and secondary mirrors. After bringing my dob in the house for a few minutes it disappears. Is this something I need to be concerned about?

Thanks.

Hi Casey,

Go for it in the winter. Many of us, most of us are concerned like you about maintaining the condition of our equipment. As much as I observed I never had any dew issues until I stopped and brought the equipment in after winter sessions. I would recommend running a small fan across the front of the tube to move air in an effort to reduce any condensation on the mirrors. I did this using a small computer type fan on my Achro's, Tak Mewlons, MT130's and APO's. Over time you may see some spots but they can easily be cleaned if they impact viewing. If they don't get in the way of your viewing leave them alone.

Kent

Casey Whalen said:

This is my first year stargazing. I have a 6" dob and i've noticed the few times i've taken it out this winter that after being outside for a while and then coming back in the house I have a fine mist or a kind of condensation on my scope. I'm mainly conserned about my primary and secondary mirrors. After bringing my dob in the house for a few minutes it disappears. Is this something I need to be concerned about?

Thanks.

Nope.
If it disappears you are good. You want to store it dry.

One can cover up the scope in an insulating covering. This will help prevent condensation from a cold scope meeting warm air. Blow drying the scope on the inside and out will work, with or without heat. Storing the scope with desiccant works. Storing the scope in an unheated area works. Or any combination of the above.

In general, dew, condensation and frost will not hurt as long as the scope is dried before storing it.

Worst case senario is to put away an ice cold dob into a warm house, in the vertical position. (Oh but it stored so much more conveniently that way!)
...I found the dried remains of the water puddles on the primary days later.