Temperature limits for scopes...

I was thinking about putting my scope on a pier (covering the scope when not in use to protect from the elements of course....) but was wondering at what temperature is the scope mirror and electronics (Celestron Nexstar 8 GPS) susceptible to damage? It can get to -15 below at night but only highs in the 80's (which of course, the highs I'm not worried about).

Thanks,

Steve

I was thinking about putting my scope on a pier (covering the scope when not in use to protect from the elements of course....) but was wondering at what temperature is the scope mirror and electronics (Celestron Nexstar 8 GPS) susceptible to damage? It can get to -15 below at night but only highs in the 80's (which of course, the highs I'm not worried about).

Thanks,

Steve
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Here's an interesting link for anyone considering leaving their scope outside...

http://www.astromart.com/classifieds/details.asp?classified_id=400224

Jon

Steve Stainbrook said:

I was thinking about putting my scope on a pier (covering the scope when not in use to protect from the elements of course....) but was wondering at what temperature is the scope mirror and electronics (Celestron Nexstar 8 GPS) susceptible to damage? It can get to -15 below at night but only highs in the 80's (which of course, the highs I'm not worried about).

Thanks,

Steve

Steve,

I would be a lot less worried about the highs and lows than in what happens when the temperature changes. The scope will cool at night, and as the daytime temperature rises parts on the telescope will lag behind and stay below the ambient air temperature. On some days the humidity will be high enough for moisture to condense on the cooler parts. Most covers, if they are really waterproof, tend to trap moisture, which makes things worse.

If you do want to store the scope outside, you want to think carefully about driving off moisture and keeping the scope dry.

Clear skies, Alan