Two On A Big Ocean The Story of the First Circumnavigation
of the Pacific Basin
in a Small Sailing Ship

      

Other Books by
Hal Roth
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Instrument Corrections

Subject: Instrument Corrections
From: Fred Hebard (Fred@XXX.XXX)
Date: Fri Mar 07 2003 - 21:26:38 EST

The calibration label on the inside of my Husun sextant box says:

  The following corrections should be applied:

Angle 30d 60d 90d 120d
Correction +20" +10" +30" +30"

After reading Bowdich and Bauer, I concluded that I should _subtract_,
for instance, 30 seconds of arc from a measurements of 90 degrees. But
I'm wondering whether I shouldn't be adding 30 seconds of arc rather
than subtracting it, for readings of 90 degrees.

Any comments would be very much appreciated.

Thanks in advance,

Fred Hebard



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