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    Re: Swinging the arc: two methods, one preferred
    From: Hewitt Schlereth
    Date: 2011 Jan 7, 00:40 -0400

    Thanks, Frank. I think I've got it. Weather permitting, I'll have a go
    tomorrow.  -Hewitt
    
    On 1/7/11, Frank Reed  wrote:
    > Hewitt, you wrote:
    > "In thinking about this technique further this afternoon, I now visualize it
    > as analogous to inverting the sextant to bring the horizon up to a star. But
    > then, instead of flipping the sextant back to "normal" you hold the scope on
    > the star and rotate the sextant around the axis of the scope. Thus instead
    > of swinging the star (sun, moon, planet) across the horizon, you swing the
    > horizon around the body."
    >
    > Yes, that's just right. Now, turn the sextant back right side up and do
    > whatever motion is required to get the same visual effect. You'll find that
    > you're turning from side to side while you're rotating the instrument. As
    > Paul has said, it's hard to describe but easy to do if you follow the simple
    > rule that the Sun or star should remain centered in the field of view. It's
    > not hard to learn at all, and it's not hard to teach if you have the
    > students right there with you. It is, however, hard to explain in words.
    > This whole business would benefit from an animation or a simple video. When
    > you've seen it done, there's nothing to it.
    >
    > -FER
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