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Celestron 130 SLT tube cap

  1. Dec 27, 2008 #1
    Just received a Celestron 130 SLT for Christmas. I haven't had a chance to use it yet due to clouds and winds. I live 15 miles east of Cleveland,OH.
    Anyways, my question is: what is the purpose of the 2" cap/hole on the 5" tube cap?

  2. jcsd
  3. Dec 28, 2008 #2


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    Staff: Mentor

    That's for cutting down the brightness when you view the moon.
  4. Dec 28, 2008 #3
    Thanks, Russ,
    That had crossed my mind, but this being my first telescope and there is no mention of it in the manual, I thought I'd ask.

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