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    Re: Short Dip distance
    From: Stan K
    Date: 2018 Mar 15, 12:04 -0400

    It may be more of a practical limit than a theoretical limit, but the dip short tables in older editions of Bowditch (American Practical Navigator) have distances as low a 0.1 nautical miles (with heights of eye from 5 to 100 feet).  The tables that were published by the United States Power Squadrons go even lower, having distances as low as 100 yards or 100 meters (with heights of eye from 3 feet to 18 feet or 1 meter to 6 meters).

    FYI, Celestial Tools includes in its Distances tool a Distance to the Horizon tool.  Enter the height of eye in feet, inches, meters, or centimeters, and it will calculate the distance to the horizon in nautical miles and statute miles.  

    Also, for all the tools that allow dip short, Celestial Tools has another feature.  From the Help:

    Note for Dip Short sights:   For a given height of eye there is a dip short distance beyond which only standard dip values (based only on height of eye) 
    are required.  If the dip short distance exceeds the distance to the natural horizon for the entered height of eye, the program will automatically switch 
    the Horizon from Dip Short to Natural.   Note that entry of the numerical portion of Ds dist. is limited to five characters, including a decimal point, which 
    should cover all reasonable values.

    Celestial Tools allows dip short distances to be entered in yards, meters, statute miles, and nautical miles.


    -----Original Message-----
    From: Bob McDowell <NoReply_McDowell@fer3.com>
    To: slk1000 <slk1000---.com>
    Sent: Thu, 15 Mar 2018 4:47
    Subject: [NavList] Short Dip distance

    What is the shortest distance that a  "short dip sighting" can be taken? I have a lake nearby that is 2 miles N&S but only 200 meters in places E&W.
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