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

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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/
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