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    Calculated slope questions
    From: Jeremy C
    Date: 2010 Dec 13, 07:34 EST
     
    I am reading a great deal about calculated slope as a means to greatly reduce the effects of random error, but I am not 100% sure I am getting the shooting methodology correct so please bear with me.
     
    If I am on a ship traveling at 18 knots and I am at twilight.  It is a good twilight and I do this method shooting three bodies 5 times each over the span of 5 minutes each (this is about all you can probably do in a given twilight without significant degradation of the horizon).  I then plot the lines and get a statistically "best fit" Hs at a time from this data.  I then reduce this Hs at the time using whatever reduction method i choose and then plot the resulting azimuth and intercept.  I will then have a cocked hat with an error ellipse which hopefully will be pretty small and thus my MPP.  Is this how it's done?
     
    My questions are thus:
    1) how does my speed affect the graphing and if so, is there an easy way to compensate for this?
    2) how long does it take people to graph these points and get the resultant data?
    3) how long does it take to calculate/plot the error ellipse "manually" ie with calculator/computer crunching the numbers but manual plotting
     
    Right now I can go from pre calculating stars to fix in about 20 minutes. This process would obviously slow me down.  The question is how much?
     
    Jeremy
       
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