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Re: Frank's method of observing
From: Frank Reed CT
Date: 2004 Aug 12, 01:32 EDT
From: Frank Reed CT
Date: 2004 Aug 12, 01:32 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
"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
