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    Default To Barlow or not to Barlow



    So here’s my question. Let’s say you’ve got a 1 ¼” 30mm eyepiece with a 62° FOV and add a 2X 1 ¼ “ Barlow. Would that reduce the FOV of the 30mm eyepiece or any wide FOV eyepiece? Is it better to get a 2” Barlow to maintain the FOV for 1 ¼ eyepieces?

    Thanks all.
    ICIt2
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    Default

    Hi welcome to the forums.
    You can download this tool:
    http://www.astronomyforum.net/downlo...?do=file&id=31

    and use it to calculate any FOV with any barlow/telescope/eyepiece etc.

    cheers
    Name: Gus OTAs: ED 100 PRO refractor, Orion ST80 (not the CF), 8" Dob stuck in Canada Mounts:HEQ5PRO Synscan mount, Manfrotto Tripod CAMS: Guidecam Philips SPC900 webcams (4), Canon unmodded-450D DSLR

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  3. #3
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    Leo
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    Default

    I asked this before but nobody answered, but only the true field of view changes, not the apparent field of view right? an barlowed Ethos will still have 100 degrees apparent field of view won't it?
    Enrico Bandolin
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    Default

    Quote Originally Posted by Leo View Post
    I asked this before but nobody answered, but only the true field of view changes, not the apparent field of view right? an barlowed Ethos will still have 100 degrees apparent field of view won't it?
    Somebody just did.

    Qs about EPs & Barlows.

    Best,

    Hernando

  5. The Following 2 Users Say Thank You to ibase For This Useful Post:

    admin (05-19-2010),Leo (05-19-2010)

  6. #5
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    Default

    Thanks everyone!

    ICIt2

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    Default

    I don't notice much of a difference in field of view, but depending on your object, barlow can be used. I don't see much of a difference when viewing DSO's, but planets and the moon have some observable differences. Also the links they gave you are very helpful.

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    5SE 4.92" f/10
    Barlows and a big set of eyepieces.

 

 

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