Dome Slit

Greetings,
For a 16" Meade Starfinder telescope, how big should the slit be in an
observatory dome to allow heat disapation, and light entering?
~ Matt

"Matt" wrote in message
m...
Greetings,
For a 16" Meade Starfinder telescope, how big should the slit be in an
observatory dome to allow heat disapation, and light entering?
~ Matt

There are those who recommend that instead of a slit, you should have dome
that retracts to expose at least half the sky.

Matt wrote:

Greetings,
For a 16" Meade Starfinder telescope, how big should the slit be in an
observatory dome to allow heat disapation, and light entering?
~ Matt

Bigger the better... The underlying principle is to minimize any
and all thermal gradients.

On 15 Nov 2003 20:09:53 -0800, (Matt) wrote:

Greetings,
For a 16" Meade Starfinder telescope, how big should the slit be in an
observatory dome to allow heat disapation, and light entering?
~ Matt

If you are going to be imaging remotely, the slit only needs to be a bit larger
than your aperture. If you are going to be working at the scope, any size slit
is very likely to produce thermal gradients and moving air. For an occupied
observatory, stay away from domes altogether and consider a rolloff, clamshell,
or other design that exposes most of the sky.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

I think a bigger concern might be to have it large enough so that you don't have to keep
moving the dome. I'd say roughly three times the size of the aperture. I did read some
estimate somewhere. It might have been in Patrick Moore's book on amateur observatories.
As for heat dissipation, cooling, and turbulence, you ought to consider forced air. Check
out such topics on Google. I think using something like "observatory laminar flow" might
do the trick. See my URL below, I may list several references on these topics. If not send
me an e-mail (see address below) or just re-post here.

Matt wrote:
Greetings,
For a 16" Meade Starfinder telescope, how big should the slit be in an
observatory dome to allow heat disapation, and light entering?
~ Matt


--
Wayne T. Watson (121.015 Deg. W, 39.262 Deg. N, 2,701 feet, Nevada City, CA)
-- GMT-8 hr std. time, RJ Rcvr 39° 8' 0" N, 121° 1' 0" W

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"Matt" wrote in message
m...
Greetings,
For a 16" Meade Starfinder telescope, how big should the slit be in an
observatory dome to allow heat disapation, and light entering?
~ Matt

Matt:
Generally dome slits should be 4X the aperture of your telescope. That
is the recommendation in the ATM series of books. You can always narrow the
slit width by closing the doors a bit unless it uses the up-and-over shutter
design. Domes are great where light pollution or wind is a problem but
aren't as quick to stabilize as a roll-off roof design. Shutters are often
opened after sunset to help with this problem.
Ed

My guess is about 36 inches, minimum. But you do not have much of a
choice if you buy a prefab dome.

Matt wrote:

Greetings,
For a 16" Meade Starfinder telescope, how big should the slit be in an
observatory dome to allow heat disapation, and light entering?
~ Matt

--
--------------------------------------------------------------
Matthew B. Ota
Orange County Astronomers Astroimagers SIG
http://www.ocastronomers.org/
Telescopes In Education (TIE)
http://tie.jpl.nasa.gov/tie/index.html
Jet Propulsion Laboratory Saturn Observation Campaign
http://saturn.jpl.nasa.gov/news/soc/
--------------------------------------------------------------

"Matthew Ota"
My guess is about 36 inches, minimum. But you do not have much of a
choice if you buy a prefab dome.

If the slit is narrow, an automated dome would fit the bill! A computer
controlled system could be devised to keep the telescope cantered in the
slit. An automated GOTO telescope would suite such a system at added
expense. Unless you have a motorized dome that can be controlled from the
observing position your going to get very annoyed, having to jump up and
turn the dome every few minutes.
Ed