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    Re: Navy MK 5 Octant Using Natural Horizon
    From: Greg Rudzinski
    Date: 2012 May 1, 10:29 -0700


    Don't get too excited over the 0.1' average intercept number. I rounded all my readings to the nearest moa plus there are uncertainties of ± 1 second of time, ± 1 ft. height of eye, and ± 0.5' on index correction. The horizon was very sharp as was the Sun's lower limb. It wouldn't take much to shift the 0.1' average intercept to 1.0' moa.

    Greg Rudzinski

    [NavList] Re: Navy MK 5 Octant Using Natural Horizon
    From: Alexandre Eremenko
    Date: 1 May 2012 02:15
    Thanks for your explanation.
    I did not realize that this was the bubble octant:-)

    (But these are excellent results for a bubble octant!
    I have never heard of the 0.1' accuracy obtained with a bubble octant,
    even if this is an average of 30)

    > There is no way to get results like I did with a
    > bubble horizon even on my luckiest day ;-)

    I thought tat there is no way to obtain the results you are talking
    about with a bubble octant at all:-)
    But I have never tried my bubble octant with the real

    > I was happy to get near marine sextant performance
    > which means that this particular octant with horizon
    > prism is good enough to substitute for a marine sextant
    > aboard ship or small craft.

    I don't see a reason to substitute a normal sextant with a bubble octant
    if the real horizon is available, except that a bubble octant is usually
    cheaper. But the performance of your bubble octant seems to be quite


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