Re: APO cooling down

From: RichA (none_at_none.com)
Date: 02/03/05 

Date: Thu, 03 Feb 2005 18:51:13 -0500

On 3 Feb 2005 09:06:28 -0800, MitchAlsup@aol.com wrote:

>"How is the cooling down of a 5" or 6" apo determined?"
>
>My 6" AP APO is cool enough when the stars images look nice and round
>and the focus is crisp. Most of the time, this is rather
>instantaneously.
 
But what kind of temperature change are you taking the scope
into? If you go from a 70deg house in summer to a 65 deg night,
yes, I can see it. If you are going into a freezing nighttime
environment, no way your scope is performing at the diffraction
limit instantaneously. Not even an 80mm apo can claim that.
-Rich

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