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    Re: I.C. and sunspot
    From: Greg Rudzinski
    Date: 2019 May 13, 12:11 -0700

    It is the artificial horizon that inverts a celestial body in the reflected image so caution to the observer when observing an upper or lower limb of a gibbous or near full moon in an artificial horizon. Sunspots would also be inverted if using an artificial horizon.

    Greg Rudzinski

    From: Greg Rudzinski
    Date: 2019 May 13, 11:37 -0700

    David,

    I stand  corrected. As you say the sunspot is twice refected so it can be used to determine index error in the same manner as a star or planet would be used.

    Greg Rudzinski

    From: David Fleming
    Date: 2019 May 13, 11:00 -0700

    Greg,

    Can you explain how the sunspot image appears in "reciprocal".  Intition tells me this is wrong.  The reflected image is twice reflected.  Experience just now looking at my neighbors house tells me this is wrong.

    DaveF

       
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