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From: Frank Reed (no email)
Date: Thu Aug 12 2004 - 01:32:38 EDT
Bruce S wrote:
"As old folks often do, I have a tremor in my hands."
Yeah, me, too. But mine's probably not so much from age as from too much
caffeine or too little wine.
And:
"Yesterday morning I gave Frank's method of observing a try. What a
difference it makes! Don't adjust the contact while holding the sextant up, just
estimate how much is needed, bring the sextant down, make the adjustment, and try
the contact again. It isn't tiring, and you can use both hands to steady the
sextant."
Glad you like it. In case anyone missed the context on this, for lunars, you
don't necessarily need to do "live" sextant adjustments since the angle
changes very slowly. Usually, I do a quick live adjustment to get the angle close,
then grab the sextant by the sides with both hands for stability and give
myself a chance to examine whether the Moon and Sun are really in contact, slightly
gapped, or overlapping. If it's not right, I lower the sextant, adjust it by
a minute or two (often less) in a comfortable posture, and then lift it up
with both hands again. Eventually you get in the habit of leaving the distance
just a touch long (assuming it's moving away from the other object) and then by
the time you have it stabilized with the objects touching again the distance
is just right. Two hands make my lunars at least twice as accurate, and I also
don't get tired of the game as quickly.
Oh, and consider sitting down when shooting lunars. This isn't cheating
--from some reports and one well-known drawing it was common practice in the 19th
century.
Frank R
[ ] Mystic, Connecticut
[X] Chicago, Illinois
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