NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Drum Sextants
From: Robert Eno
Date: 2005 Jun 15, 19:15 -0400
From: Robert Eno
Date: 2005 Jun 15, 19:15 -0400
Gidday Mike,
I agree with you on the need for tenths when taking
lunars, however, my only experience in taking lunars -- and I have taken a lot
-- is on dry land from a rock-solid platform. In this case, it was useful
to be able to read my sextant to the nearest tenth of a minute. But what about
taking lunars at sea? I suggest that even for lunars, being able to
resolve angles to the 0.1 minute of arc is expecting too much given the
circumstances.
Then again, just because it is beyond my capabilities,
doesn't mean that there are not a bunch of crack shots out there who can salvage
a star sight in a hurricane.
Robert
----- Original Message -----From: Mike BurkesSent: Wednesday, June 15, 2005 3:48 PMSubject: Re: Drum SextantsTenths have their places in Lunars and if observer requires surveyor accuracy all on land of course.Quick correction on my C.Plath description:You can resolve the measurement to the nearest tenth when two vernier lines on the fixed portion are bracketed by two vernier lines on the rotating drum.I got it arse-backwards in my first comment.
