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    Artificial Horizon Obs. using Camera w/Bris
    From: Greg Rudzinski
    Date: 2014 Feb 1, 09:13 -0800

    The attached is a morning artificial horizon observation of the Sun using a DSLR 50mm equipped with microscope slide Bris reflector. From left to right is #8 reflected Sun, artificial horizon direct Sun (blue), #7 reflected Sun, and #6 reflected Sun.

    For those who would like a go at reduction:

    UT 13:36:20 1 Feb 2014
    aLat 27° 41.1' N
    aLon 80° 24.0' W
    Sun dia. 32.46'
    #8 Sun reflection 36° 2'
    #7 Sun reflection 32° 23'

    Divide total measurement by 2 to get Hs. Measure Sun center to Sun center rather than from the limb because of the elongated reflected images. Measuring with a millimeter rule on a zoomed image should be good enough (2'-3')or count pixels.

    Greg Rudzinski

    P.S. Very happy with my new photoshop (Lightroom 5) software which works with raw images.

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