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Sextant Errors


Subject: Sextant Errors
From: Robert Eno (enoid@XXX.XXX)
Date: Sat Jun 22 2002 - 19:14:31 EDT


I am somewhat ashamed to ask this question, having been a sextant user for many years, but here goes:

1. What are the consequences of not having the index mirror exactly perpendicular to the sextant frame (error of perpendicularity)?

2. What are the practical consequences of not totally eliminating side error?

I should add that a very experienced instrument repair man (now deceased) from Baltimore once told me that in fact having a bit of side error was beneficial, particularly when using a star to determine index error; the rational being that it is much easier to judge when the star images are side by side rather than superimposed. My own experience tells me that the latter is true but does not answer my original question.

Can anyone answer the above two questions? I have yet to see a navigation text that actually addresses this.

Cheers,

Robert





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