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Re: Problem with a sextant

From: Alexandre E Eremenko (no email)
Date: Mon Apr 24 2006 - 12:11:58 EDT

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    Ken,
    Thanks. That I may try at some point, though I never messed
    with index adjustment before.
    My immediate plan is to measure small star distances,
    2,3,... to 9 degrees, to see where the problem exactly is.
    The smallest star distance I measured so far was about 10
    degrees and it already has error about -0.9' (as most of the
    other star distances)
    while the index error is probably -0.3, but definitely not
    more than -0.6'. Thus something happens between 0 and 9 degrees.

    Alex

    On Mon, 24 Apr 2006, Ken Muldrew wrote:

    >
    > On 24 Apr 2006 at 10:17, Alexandre E Eremenko wrote:
    >
    > > The only explanation I can imagine is that the arc is deformed near 0.
    > > (Worn after so many index checks, as Bill joked:-) Inspection of the arc
    > > and teeth with powerful magnifying glass shows no defect.
    >
    > You could put the mirror way out so that your index error is about 2
    > degrees and see if that helps.
    >
    > Ken Muldrew.
    >


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