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    Re: Shadow sights for longitude
    From: Peter Monta
    Date: 2018 Jan 12, 20:43 -0800

    Increaseing shadow length will not improve the accuracy.  As has been noted the accuracy is limited by the sun not being a point source of light.


    Would "shadow sharpeners", as used by the sundial people, be of any help?  A moderately-large pinhole is placed in the shadow near the surface, then moved until the image shows a half-sun.  Then you're centered at the halfway-point of the shadow, which would otherwise be difficult to locate by eye.

    Cheers,
    Peter

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