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    Re: Navy MK 5 Octant Using Natural Horizon
    From: Greg Rudzinski
    Date: 2012 May 2, 12:41 -0700

    The best way to figure index error for a bubble octant is to use Gary LaPook's Polaris method (see archive). Observe Polaris at zero LHA or 180 LHA. You can also take 30 observations in a row then average and apply an I.C. that gives a 0.0' intercept that compensates for the average intercept.

    The natural horizon prism and bubble horizon are separate and require separate trials for determining I.C.

    Greg Rudzinski

    [NavList] Re: Navy MK 5 Octant Using Natural Horizon
    From: Alexandre Eremenko
    Date: 2 May 2012 14:59
    Look like very good resuts (for a bubble) to me.
    The sky just cleared in Indiana, let me try some bubble observations
    with my MkIX A.
    I conclude from your messages that your IC is different for the horizon
    and for the bubble.

    I never measured my octant bubble IC. How do you do this?
    Neither I measured it with a horizon, because a horizon is something
    I see very rarely in my life:-(

    On the other hand I never detected any systematic error.


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