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    Re: Using the sun's direct and reflected image to determine a sextant's IE
    From: Antoine Couëtte
    Date: 2020 Mar 11, 12:09 -0700

    RE : Using-suns-direct-reflected-image-determine-sextants-IE-TonyOz-mar-2020-g47215

    from which clearly follows if we want to know the TRUTH we must do APPARENT + INSTRUMENT ERROR

    Not so sure ...

    From a recording you either :

    - Remove (i.e. "subtract") an error, or

    - Perform (i.e. "add") a correction.


    PS : To determine Sextant IE, rather than using the Sun which is extremely sensitive to "lateral offset" between both images because of non-zero apparent diameter, much better use a low altitude star : disregard the images offset and when both images are at the same level (do keep your sextant vertical), then you immediately read IE, in a much more expeditious and reliable way, as long as offset is not too big in which case you need to fine-tune your sextant.

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