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Old 29-10-2011, 10:19   #16
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Re: Taking Multiple Sun Shots

Every mariner worth a salt should learn celestial in my opinion. But when the weather turns nasty and you've lashed yourself to a little boat in a big ocean, thank goodness for GPS. To ignore modern technology is just silly, and I consider myself from the "old school" when it comes to this kind of stuff. But to become overly reliant on it would be equally foolhardy.
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Old 29-10-2011, 10:41   #17
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Re: Taking Multiple Sun Shots

10 am x3
noon
2pm x3

3 to validate 2 of them are close enuf

for fun: sunrise and sunset
for surprises and speed: moon
for mathematical frustration: lunar distance

Never was very good with stars and planets.
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Old 29-10-2011, 10:50   #18
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Thumbs up Re: Taking Multiple Sun Shots

[QUOTE

*Ever notice how everyone stops chatting about a week in?[/QUOTE]

William Buckley's classic book "Atlantic High" notes that what makes a long passage most memorable is the character of the crew (their knowledge, experience, etc.). An otherwise boring passage becomes a stimulating intellectual exercise if the captain selects the proper crewmember/guests.
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Old 29-10-2011, 14:34   #19
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Re: Taking Multiple Sun Shots

If the satellites were ever shut down, you will not need sextant eider, believe me. you will have nowere to go

regarding sights,i am taking only noon sight and polaris sight. more than enough (et least for me). and sometimes using sextant to find position by sighting lighthouses.
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Old 29-10-2011, 15:36   #20
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Re: Taking Multiple Sun Shots

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If the satellites were ever shut down, you will not need sextant eider, believe me. you will have nowere to go

regarding sights,i am taking only noon sight and polaris sight. more than enough (et least for me). and sometimes using sextant to find position by sighting lighthouses.
Without the gps satellites we don't have much. I tossed my old RDF but I do have a very good Loran set. Anybody like to buy the Loran????
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Old 29-10-2011, 15:53   #21
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Re: Taking Multiple Sun Shots

Usually a noon site, then Venus or the moon depending.
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Old 29-10-2011, 16:31   #22
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Re: Taking Multiple Sun Shots

I take a morning one and then a noon one. If the morning one was not possible and the noon one was, then I take an afternoon one. If the noon one was not possible I call it a day.

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Old 30-10-2011, 11:28   #23
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Re: Taking Multiple Sun Shots

Quote:
Originally Posted by Seaduction View Post
[QUOTE

*Ever notice how everyone stops chatting about a week in?
William Buckley's classic book "Atlantic High" notes that what makes a long passage most memorable is the character of the crew (their knowledge, experience, etc.). An otherwise boring passage becomes a stimulating intellectual exercise if the captain selects the proper crewmember/guests.[/QUOTE]

I was crew, not the skipper. The object was helping to move a boat offshore, not Buckley levels of wit.

Nonetheless, I concur that would be my choice, too.
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Old 30-10-2011, 11:37   #24
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Re: Taking Multiple Sun Shots

Welcome to the forum bajardine.
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Old 30-10-2011, 11:40   #25
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Re: Taking Multiple Sun Shots

It has been a very long time since the sewing machine was invented. Even so, sailors still need to know how to use a needle and palm. So also, even though we live in the age of GPS, celestial navigation is something that a compitent sailor needs to know. It's just one part of the whole package of skills that makes a compitent sailor/navigator/pilot.
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Old 30-10-2011, 12:24   #26
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Re: Taking Multiple Sun Shots

*Ever notice how everyone stops chatting about a week in?

I've found conversations get more interesting, the longer the passage. But then I single hand.
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Old 30-10-2011, 12:49   #27
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Re: Taking Multiple Sun Shots

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[I](...) I've found conversations get more interesting, the longer the passage. But then I single hand.
OMG ;-)

This is exactly what admiral says about my neurotic monologues!

Cheers,
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Old 30-10-2011, 13:19   #28
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Re: Taking Multiple Sun Shots

FWIW,

Back in our celestial days I used a bit of old software called PC Nav (or similar). It was a tiny (by windows standards) DOS code that fit on a single floppy. It would allow one to take multiple sights, apply DR for the time period involved and do a bit of smoothing before finding a weighted value for time and altitude. Also showed you if here were any outliers (bad shots) and allow you to discard them. Had a built in star finder as well as all the astral data from the almanac... really cool, and the results were quick and pretty damn accurate. I loved it!

Also had a small program for noon sights that would do a least squares fit to a parabola. That one ran on an HP-41 and gave one a reasonable longitude from the noon sight... but I digress!

My point is that if you have some means of using the extra data, multiple sights can indeed be useful.

Cheers,

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Old 30-10-2011, 13:56   #29
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Re: Taking Multiple Sun Shots

After a while you get a feel for how good a shot is, sometimes I'd take 5-6 then only use the last one.
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Old 30-10-2011, 15:28   #30
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Re: Taking Multiple Sun Shots

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*Ever notice how everyone stops chatting about a week in?

I've found conversations get more interesting, the longer the passage. But then I single hand.
I suppose it beats a murderous argument!
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