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Re: HO 211 Sadler Technique
From: Stan K
Date: 2014 Mar 9, 22:14 -0400
From: Stan K
Date: 2014 Mar 9, 22:14 -0400
Thanks, Paul. I already incorporated the Sadler Technique into Celestial Tools, for both the original and compact versions of 211. V4.4.0 Beta 9 should be on the web site tonight or tomorrow. I think it works fine, but it might need some cosmetic help.
I know several people who feel the same way about Ageton-Bayless as you do. I, for one, never understood the need to go from a small book to a slightly smaller book, with the resultant possible confusion.
Stan
I know several people who feel the same way about Ageton-Bayless as you do. I, for one, never understood the need to go from a small book to a slightly smaller book, with the resultant possible confusion.
Stan
-----Original Message-----
From: Paul Hirose <cfuhb-acdgw@earthlink.net>
To: slk1000 <slk1000@aol.com>
Sent: Sun, Mar 9, 2014 4:57 pm
Subject: [NavList] Re: HO 211 Sadler Technique
From: Paul Hirose <cfuhb-acdgw@earthlink.net>
To: slk1000 <slk1000@aol.com>
Sent: Sun, Mar 9, 2014 4:57 pm
Subject: [NavList] Re: HO 211 Sadler Technique
"Compact Sight Reduction Table" by Allan E. Bayless, a modified HO 211,
shows the Sadler technique with this example:
89° 06′ t B 180390 A 5
53° 16′ S dec A 9614 +B 22323 +B 22323
33° 19′ S lat +A 26022 +B 7798
-----
26° 07′ h1 A 35636
26° 35′ Ho
-------
52° 42′ h1+Ho
26° 21′ (h1+Ho)/2 -B 4764
------
0° 30′ h2 A 205747
-------
26° 37′ hc = h1+h2 -B 4865
-----
41° 59′ Z A 17463
With a calculator I get Hc = 26° 37.1′ and Z = 41° 59.0′.
Speaking of the Bayless table itself, I don't like it as well as the
Ageton table in Bowditch vol. 2. (I don't own a "real Ageton".) To cut
the table size in half, Bayless goes up to 45° instead of "turning
around" at 90°. This is possible because of the symmetry of the trig
functions, e.g., sin 80° = cos 10°. Thus the table need only go as high
as 45°. However, it requires a double heading at the top and bottom of
each column. Depending on the angle, the left hand column can be either
the A or B value of the angle.
On the other hand, the table in Bowditch always has the A value on the
left and B on the right. In addition, the B column is boldface. These
things help you avoid blunders.
The other thing I don't like about Bayless is that he omits the leading
digits when they are the same for several consecutive entries. For example,
33925
901
876
852
827
so you have look in two places to get all the digits.
--
