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    Re: Fix differences with 5 reduction methods...Read "clarifications"
    From: David Fleming
    Date: 2014 Jan 15, 15:58 -0800


    Let me try to be clearer about your comparison of sight reduction methods.

    First though I've used at least 4 different sight reduction methods for obtaining Line of Position results I have not done a comparative study of the methods. Such a study would reveal that they differ in the number of data points in their tables, complexity of rules for signs around entries based on how the problem has been "folded" to reflect symmetries that reduce table sizes, and perhaps that the method produces unreliable results as altitudes approach 90d for example. They also differ in using a DR or an AP.

    What my intuition tells me however, is that they will not differ in the Line of Position that they produce by more than at most a few tenths of a minute of arc seperation between parallel LOPs. To produce larger errors is unacceptable for celestial navigation results.

    My preference is to use a calculator. It feels like I am doing it myself, though I didn't build the calculator.

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