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    Re: Logic of shades
    From: Mark Coady
    Date: 2018 Oct 27, 12:13 -0700

    I am sure there are other good reasons such as vis and haze and differing light. I will leave that to the experts.

    One practical app I experienced.

    If you set index error using the sun diameter method, I love the fact my astra IIIb can change the direct and reflected image colors. OK...I'm a simple mind....but it makes the two image edges distinct as I bring them together.  My C & P does not change the two images and I find it more difficult.

    A minor thing, especially as a majority of my sights are from terrafirma and I use the aproach I learned from Frank Reed of zeroing  out index error using a spotting telescope.


    Lat 41.323 Lon 71.994 W

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