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    Re: Shadow sights for longitude
    From: David Pike
    Date: 2018 Jan 13, 00:02 -0800

    David Fleming wrote:  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. 

    I think we’re talking about two different error sources here.  There’re the difficulties caused by the Sun not being a point source of light and also the difficulties in measuring the base and the perpendicular of our triangle accurately, even if the Sun was a point source.  Size won’t improve the former although it might make that difficulty more obvious, but it can improve the latter.  DaveP

       
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