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    Re: An artificial horizon opportunity?
    From: Frank Reed
    Date: 2017 Jan 27, 17:54 -0800

    David Pike, you wrote:
    "Presumably, if the observer faced directly at the Sun, the reflection would fall exactly below the real Sun."

    But the observer is facing the Sun. The observer is contemplating a lake full of tasty fish... (you guys noticed the cat, right?).

    But I'm glad you mentioned that reflection alignment issue. What's going on in this photo? The reflection of the Sun is always supposed to fall directly below the Sun regardless of the observer's orientation. So why is it offset in the photo? Could it be fake? I considered this possibility initially. Perhaps an artist mirrored the background to create the illusion of a perfectly calm lake. But then when you consider the fine lines of the cat's fur and whiskers, that starts to look much too complicated ...not fake. My best guess is that the photo was was adjusted in post-processing (or maybe it's a lens distortion). Anyway if you apply a vertical perspective adjustment, you can get it all to line up right. Not that there's any point to this... just a confirmation that the offset is reproduced in a simple way. See attached images.

    Frank Reed



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