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    Re: NASR question on large F values
    From: John Pinto
    Date: 2021 May 27, 16:47 -0700

    So far I haven't seen a realistic example where using the NASR tables you get a large negative F value from a ship at Sea.

    Other than the Polaris sight (which may not be realistic) can anyone come up with anything else?

    I've been told the only realistic  sights where F is negative is very low Sun sights of the Upper Limb at sunrise or sunset but I have not been able to produce a realistic example of this where the negative F is large, mostly -1° or -2°.

    If there is no realistic examples of large negative F values, then step 8 in the NASR procedures and form for adjusting the Z2 value should be interpreted as three mutually exclusive cases:

    1) F > 90 (and thus make Z2 negative) - I assume we are ignoring the sign of F in this case but I could be wrong 

    2) F is negative (and thus make Z2 = 180 - Z2)

    3) All other values of F leave Z2 as is

    Would someone please confirm or correct me on this?

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