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    Default help! if you buid a telescope with a focal length of 1.3 m, what focal length...



    ...should the eyepiece have to..? give a magnification of 100 times?

    help!! how do i answer this question?

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    Default

    Quote Originally Posted by marykate View Post
    ...should the eyepiece have to..? give a magnification of 100 times?
    f(eyepiece.)= f(objective) / magnification = 1300 / 100 = 13 mm

    M (magnification) = f(objective) / f(eyepiece.) = 1300 / 13 = 100 x

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    Default

    Quote Originally Posted by marykate View Post
    ...should the eyepiece have to..? give a magnification of 100 times?

    help!! how do i answer this question?
    Another homework/exam question? How did AT.net get onto the homework help short list?

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    Default

    MaryKate

    The Sky and Telescope Web Site has an article about telescopes that explains not only how to calculate the power of a telescope but just abount any other thing about telescopes that you wish to know. The article is not written in technical language and is easily understood. Also in the article is an online telescope power calculator. Here is a link to the site. It is free to the public: SkyandTelescope.com - Choosing Your Equipment - How to Choose a Telescope
    SXINIAS

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    ZEQ25 mount;
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    SynScan AZ
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    Mount;

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    ST-80A 80mm Refractor (OTA); Meade
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    203mm SCT (OTA);
    Meade DS2090AT 90mm Refractor; Meade 2045LX3 102mm SCT;

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    4 SE 102mm MAK; Celestron Advanced Series C6S (XLT) 150mm SCT
    with an iOptron GOTO Drive

    My Photos:
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