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    Re: Sextant Scope Parallelism (was Re : SNO-T Sextant)
    From: Bruce Stark
    Date: 2004 Aug 14, 20:14 EDT

    You wrote:

    That’s where you got me.
    If the sextant is vertical you are measuring the
    correct angle. If the scope is pointing off center by a small amount then
    you see the sun a little displaced from the center of the scope. But isn’t
    the sun still in the center of the horizon mirror and therefore in the right
    place for the measurement.  If you insist on keeping the sun in the center
    of the scope I don’t think that you can get the sun to the bottom of the
    arc, it will wander off center as you get to the bottom.  Can you force it
    both to the center of the scope and the bottom of the arc at the same time
    if the scope is out of Parallelism?"

    Although I think I could answer your question, there's a good chance I'd confuse things further, or even be dead wrong. I'd rather leave it to someone who understands optics better than I do.

    Will another List member pick this up?


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