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    Re: What is the best accuracy you can expect from a 'dip-short'table
    From: Jeremy C
    Date: 2014 Oct 22, 09:41 -0700

    I've used it when ships are under the star I want to shoot (typically when relative speed is very small). I have also used it along non-discript land where a range can be obtained, but not a clear bearing.  I have also used dipshort when I am shooting a particular body and it passes over land (e.g. transit of a body).  Fog in convoy is a great idea that I had never considered before.  Of course all of my sights are "nice to do" things.  

    That being said, range is best determined by radar which is what I do.  You could also use a rangefinder, but those are pretty rare on ships that will over the required range.  If the obstruction is of known height, you could also use the sextant to determine height of an object and thereby determine range.  I have also heard of using sound signals and timing the echo, but I've never done it myself.

    If I get the range correct, I find that the tables in bowditch give me no more appreciable error than I would expect if I was using a sea horizon. That has been my experience.  However, most people wouldn't bother to shoot stars if there was an obstruction.

    JCA

       
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