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  1. #1
    Crazyhair's Avatar
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    Default Barlow Eyepieces



    I've been shopping for a Barlow lens but till now didn't know there were more choices than 2X. Now I see 3X & 5X. I'm guessing anything above a 2X is probably over kill.

    What's the thought here - O Great Guru of the eye pieces!

  2. #2
    dmbryan's Avatar
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    Default

    Start with the 2x. That is probably all you will ever want.
    name: Derek

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  3. #3
    Crazyhair's Avatar
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    Default

    Thanks, that's what I was thinking!

  4. #4
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    Default

    The question is "Why 2X barlows?"

    If you acquire a number of EPs and space the focal lengths in a ratio of 2/3 or 3/2 a 2X barlow doubles the number of EP focal lenghts you have without duplication.

    For example: start with a 30mm EP, *2/3 = 20mm, *2/3 = 13mm.
    Add a 2X barlow and you now have: 30mm, 20mm, 15mm, 13mm, 10mm, 6.5mm.

  5. #5
    tjbdallas's Avatar
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    Default

    I have pretty good 2x and 3x barlows. I found that the 3x was overkill and the 2x was just fine.

    Terry

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    Meade 8"
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    EON 80mm, ETX90, LPI, ToUcam 740, DSI Pro II, Unpaid bills

 

 

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