Do you warm a telescope?

Ammar Majeed wrote:

Hi all,
it might be a stupid question to ask here, but since i never had a telscope
before and since i am planing to buy my first now so i might ask this...
why do you need to cool a reflector ( and not a refractor)??
Thanks for the answer
Amma

Here's the opposite question. Do you warm your telescope? I live in the
mid-Ohio valley. It's not as hot as a desert but there is some humidity. By 10
PM the temperature is 85F and the dew point is sometimes as high as 72F. This
is just under the temperature of my basement where I keep the telescope. It
seems there's a chance condensation could form if I take the telescope
straight outside from the basement. Perhaps I could use a room heater to warm
it up some first.

-Frank

Frank Glandorf wrote:

Ammar Majeed wrote:

Hi all,
it might be a stupid question to ask here, but since i never had a telscope
before and since i am planing to buy my first now so i might ask this...
why do you need to cool a reflector ( and not a refractor)??
Thanks for the answer
Amma

Here's the opposite question. Do you warm your telescope? I live in the
mid-Ohio valley. It's not as hot as a desert but there is some humidity. By 10
PM the temperature is 85F and the dew point is sometimes as high as 72F. This
is just under the temperature of my basement where I keep the telescope. It
seems there's a chance condensation could form if I take the telescope
straight outside from the basement. Perhaps I could use a room heater to warm
it up some first.


Just as letting a cold scope that's been outside in the wintertime
simply warm up until the condensation evaporates, the same principle
applies here when going from cool basement to warm outside.

So, if you want to get down to observing business sooner, your best bet
is simply moving it upstairs first and letting it warm up prior to
taking it outside.
--
Mike
http://www.concentric.net/~richmann/

In article ,
Frank Glandorf wrote:
Ammar Majeed wrote:

Hi all,
it might be a stupid question to ask here, but since i never had a telscope
before and since i am planing to buy my first now so i might ask this...
why do you need to cool a reflector ( and not a refractor)??
Thanks for the answer
Amma

Here's the opposite question. Do you warm your telescope? I live in the
mid-Ohio valley. It's not as hot as a desert but there is some humidity.
By 10 PM the temperature is 85F and the dew point is sometimes as high
as 72F. This is just under the temperature of my basement where I keep
the telescope. It seems there's a chance condensation could form if I
take the telescope straight outside from the basement. Perhaps I could
use a room heater to warm it up some first.

....or perhaps you can just bring it outside? That's the easiest
way to warm it up. Any condensation which may form will quickly
evaporate ... after all your dewpoint is well below your outside air
temperature.

--
----------------------------------------------------------------
Paul Schlyter, Grev Turegatan 40, SE-114 38 Stockholm, SWEDEN
e-mail: pausch at stockholm dot bostream dot se
WWW: http://www.stjarnhimlen.se/
http://home.tiscali.se/pausch/

Michael Richmann wrote:

Frank Glandorf wrote:

Here's the opposite question. Do you warm your telescope? I live in the
mid-Ohio valley. It's not as hot as a desert but there is some humidity. By 10
PM the temperature is 85F and the dew point is sometimes as high as 72F. This
is just under the temperature of my basement where I keep the telescope. It
seems there's a chance condensation could form if I take the telescope
straight outside from the basement. Perhaps I could use a room heater to warm
it up some first.

Just as letting a cold scope that's been outside in the wintertime
simply warm up until the condensation evaporates, the same principle
applies here when going from cool basement to warm outside.

So, if you want to get down to observing business sooner, your best bet
is simply moving it upstairs first and letting it warm up prior to
taking it outside.
--
Mike
http://www.concentric.net/~richmann/

My usual procedure when moving the telescope inside is to seal it up in plastic.
Mostly this is to keep out the dust. In the winter it also prevents condensation by
sealing out the warm, moist room air. As the cold air in the telescope warms, it
expands and should push out the room air. Warming or cooling a sealed tube takes
awhile so I don't use this procedure when taking the telescope outside.

I also assume that condensation on the mirror is undesirable. This may not be
valid. The mirror gets an annual bath but I'm not sure condensation from our smoggy
skies is as clean as distilled water. However I don't have any way to quantify my
assumptions.

-Frank

Here's the opposite question. Do you warm your telescope? I live in the
mid-Ohio valley. It's not as hot as a desert but there is some humidity.
By 10
PM the temperature is 85F and the dew point is sometimes as high as 72F.

Yes! Here is a DIY circuit that warms the telescope and automatically keeps
it (or optics) a small amount above ambient
http://mysite.verizon.net/res0owmd/id1.html

Don Clement
Running Springs, California
http://www.clementfocuser.com