Re: [ATM] asymptote to ambient

["Don Clement" <clement.focuser@verizon.net>]

> I read in a recent review of dew heaters that a mirror can drop below
> ambient by radiative cooling.  If this is also below the dew point, dew
> forms.  So by considering only conduction with the air, the approach to
> ambient is asymptotic.  But by adding in radiative cooling, it is
reachable.

Sounds like mirror temperatures can be all over the place. Above ambient -
below ambient -  thermal gradients within the poor thermally conducting
glass   How close to ambient does the mirror have to be to not effect
seeing? If the air in front of the mirror is sufficiently homogenized, is a
large deviation of mirror temperature from ambient moot with respect to
seeing effects?

Don Clement
Running Springs, California

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