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    Re: Polaris in daytime
    From: Greg Rudzinski
    Date: 2012 Jan 25, 16:29 -0800

    Geoffrey,

    I use a 4x40mm scope when attempting difficult day time Venus, Jupiter, or Sirius observations.

    Greg Rudzinski


    [NavList] Re: Polaris in daytime
    From: Geoffrey Kolbe
    Date: 25 Jan 2012 16:44
    Hello Greg

    Yes, its photons that counts. If Sirius is 23 times as bright then I
    need an object lens that is about 4.7 times the diameter of yours.
    (4.7 is the square root of 23)

    So, can you tell me how big your object lens is?

    Thanks

    Geoffrey

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