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Thread: eyepieces

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    Default eyepieces



    hey i only have 2 eyepieces for my scope right now i should have many more on the way but i just wanted to know about them. I have 1-10mm and 1-20mm when i look at the moon i thought the higher mm would go closer but it shows more is this right?

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    Default

    The "higher mm" or 20mm would not "go closer," the lower mm (10mm) will have more magnification if that is what you meant when you said "go closer." But yes, the 20mm will "show more," or a bigger slice of the Moon because its magnification is lower than that of the 10mm eyepiece.

    Example, for an 8" SCT F/10 telescope with a focal length of 2032mm:

    Eyepieces = plossls (52-degree apparent field of view) - 10mm & 20mm's

    Magnification:
    10mm eyepiece = 203.2x
    20mm = 101.6x

    True field of view:
    10mm eyepiece = .256 degrees
    20mm = .512 degrees

    The 20mm eyepiece with a .512 degrees or half a degree view can fit the full Moon inside the view, while the 10mm eyepiece with a .256 degree view can only fit half of the Moon inside the view.

    Use this to calculate the magnification and true fields:

    Telescope Eyepiece Comparator

    Hope this helps.

    Best,

    Hernando

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    Default

    thanks much help

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    Default

    Just curious, did you enjoy the view better with more magnification (10mm eyepiece), or with a larger field of view (20mm eyepiece)?
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    Default yes

    yes i did i found that the 32mm help me find much better as my starpointer is not yet done but i need to fix that and i got some nice view of jupiter and 3 of its moons but i am going out 2night to night.

 

 

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