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svHyLyte · 04-03-2008, 08:56

The entry would be 30.4160, i.e. degrees separated from minutes by a decimal point. Minutes are whole minutes and then tenths and hundredths.

For example, 30 deg 4.65 minutes would be entered 30.0465.

Frankly the extra precision really doesn't add a lot to the process. You're generally looking at one minute per mile and most people can't get a sextant reading from the deck of a small boat that's more reliable then one minute. With lots of practice maybe .5 minutes. For star sights with a good horizon and 3 stars about the best an experienced person can do is about 1000 yards of an actual position. Sometimes better but usually not. With good conditions I generally assume my circle of error is about a mile or so in radius which is usually close enough.

Cheers,

s/v HyLyte

04-03-2008, 08:56	#6
svHyLyte Registered User Join Date: Mar 2006 Location: Tampa Bay area, USA Boat: Beneteau First 42 Posts: 993	The entry would be 30.4160, i.e. degrees separated from minutes by a decimal point. Minutes are whole minutes and then tenths and hundredths. For example, 30 deg 4.65 minutes would be entered 30.0465. Frankly the extra precision really doesn't add a lot to the process. You're generally looking at one minute per mile and most people can't get a sextant reading from the deck of a small boat that's more reliable then one minute. With lots of practice maybe .5 minutes. For star sights with a good horizon and 3 stars about the best an experienced person can do is about 1000 yards of an actual position. Sometimes better but usually not. With good conditions I generally assume my circle of error is about a mile or so in radius which is usually close enough. Cheers, s/v HyLyte __________________ "It is not so much for its beauty that the sea makes a claim upon men's hearts, as for that subtle something, that quality of air, that emanation from the waves, that so wonderfully renews a weary spirit."