Re: dew heater

From: Manuel Joseph Din (din_at_spam.colo.edu)
Date: 12/03/04 

Date: 3 Dec 2004 02:11:24 GMT

MoFoYa wrote:
> I live in a VERY humid area (Texas Gulf Coast), so dew is a big problem.
> Can anyone recommend an inexpensive solution for an 8" SCT? I am thinking
> about making my own heaters, but would rather pass on all the work if there
> is a cheap alternative that functions reasonably well. In the meantime the
> hair dryer thing keeps me observing, but it's a pain in the a**. It seems
> like I spend more time looking at my scope rather that through it.
>
> TIA for any ideas,
> Tommy
>
>

Have you tried wrapping your scope in Reflectix (TM) double bubble
reflective insullation foil? Two layers of mylar foil block emissivity,
two layers of polyethelene bubbles block conduction. An excellent
insullator. I bet it would make a HELL of a dewshield. In fact, I am
going to drag my sorry ass down to home depot (or some similar merchant)
this weekend and make a complete zero emission scope-wrap-blanket and
super-bolic mega-extension dew shield for my C-8.

When I have completed the project, I will post a link to photos and
results of the insullation installation.

I figure the biggest contributor is radiant cooling of the aluminum
scope tube, which I believe is responsible for getting the scope below
the dew point. (Which is probably 99F on the Gulf Coast, right? Heh.)
Once your scope and optics hit dewpoint, all bets are off. Below
dewpoint and you have a still, not a 'scope. ;-)

Clear Skies,
Uncle Bob
How'd ya like that "super-bolic" descriptor? I just made it up.

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