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Zhumell 3x Barlow

  1. Jan 15, 2008 #1
    Sorry to be starting a new topic yet again, hope I don't look like a post whore:

    I'm thinking about buying this barlow but first I have some questions.

    1) Will I be sacrificing a lot of image quality (if any) in using a 3x barlow? My scope is a 12" Dob.
    2) Will the barlow simply triple the size of the image I see without it, or will it make other things visible that weren't before?
    3) Is it really worth it to buy a 3x barlow rather than a 2x?

  2. jcsd
  3. Jan 15, 2008 #2


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    Gold Member

    You need to think about your current EP line-up. I chose my EPs based partly on my choice of Barlows. If you have a 2X and a 1.5x, you've got a real mix-up depending on what EPs you choose. Make up a little spread-sheet of the available magnifications. Remember that some EPs have pretty nice eye-relief, and that this wonderful feature is still available when you've got the EP stacked in a Barlow. It makes a difference.
  4. Jan 15, 2008 #3


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    Staff: Mentor

    Also, for your #2, a Barlow will reduce the brightness of the image, so less things will be visible, not more.
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