NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Dip
From: Fred Hebard
Date: 2004 Dec 1, 23:25 -0500
From: Fred Hebard
Date: 2004 Dec 1, 23:25 -0500
On Dec 1, 2004, at 1:06 AM, Alexandre Eremenko wrote: > By the way, Shufeldt in his paper > "Irradiation and refraction at low altitudes and the working > navigator" (Journ of The Inst. of Nav., 4,2, 1954) claims that.... > > One place in this paper was expecially interesting for me: > he says that > > "to my surprise, attempting to establish index error with > a close degree of accuracy proved to be the most difficult > part of the whole operation". > > This is very well confirmed by my own experience. > (I recently posted the data of such observations). > Unfortunately, he does not try to explain why this is so. > > Alex. > > Alex, That's also my impression, and the difficulty is holding the sextant sideways. Fred
