NavList:

Amplitude.
No contest amplitude is best to me. The books and training in the Navy lock in the azimuth as the way to check compass
because of longtime use their teaching and books all agree.
Could they be wrong? I say yes. Because of my many years of evaluation of both Amplitude and Azimuth.
I can understand many reasons (no good reason) for their selection.
One. The books say so! Two. The azimuth can be obtained in the yards as well as at sea, so it is usually available, where the bearings and NavAids
are limited to near land!
Three. The azimuth uses difficult equipment and tables, with bubbles and a thick light beam onto the compass card for comparison and you may
think you are accurate!
(I wonder if the present writers every chased the bubbles, did the Azimuth or did they just pass the word on from past writers.)
four. The books all agree that all LOP’S are equal and positioned the fix in the center of a cocked hat. This may be my belief only?
Why do I disagree? One. I say the my technique and bearings take the mystery out of compass error. Two. The bearing circle shooting a low-level target
can be down to 0.1/0.2 accuracy ( don't forget the azimuth circles 0.3 degree light beam wide and bubble moving around even tied up in port.)
Three. The amplitude needs little or no interpolation for latitude and declination until you go away up North.
The azimuth and tables require a three-way interpolation.
Four. The height of eye causing the difference between the visual horizon and the celestial horizon is very small,
I make this judgment by inspecting the corrections of the Nautical Almanac and NO. 9 volume 2, table 28 “Amplitude correction on the visible horizon.”
Five. The refraction possible error is very small in the horizontal bearing for the same reason as Four.
The U.S. Navy requires a fix every three minutes from their navigation team, unlike the Merchant they have the men for the team.
I don't believe any other ship Navy or civilian has this requirement.
This is why I developed that Franklin piloting technique and why looked at the nuts and bolts and geometric of compass error
and dislikes the use of the azimuth for aligning the Gyro system.
I have found that compass error compass exsit on a large number of ships because of using and aligning with the azimuth circle as the reference.
I boarded many ships and was told that the ship had no compass error, even when a good size error existed and could be seem on the chart plot.
In answering about daily azimuth for the Navy, yes, when weather permits and yes the magnetic compass is called standard compass
and must be compared and logged every one half hour and every change of course at sea
. The standard compass although not accurate is always working and reliable.
I used my star finder to evaluate the degree of change between one body on my Meridian and another on my horizon, my latitude of 45 N
. While on my Meridian 180° south of me, moved to 190 (10° ) the body on the horizon only moved less than 5° this is what I talked
about in my previous writing when I said body moving towards and away from you change slower.
I used my star finder to get comparisons of amplitude reading from my horizon of 45°N and various declinations for 3 other bodies.
My star finder was around 1° error from the 3 computed bearings. You can use the 2102-D in the same way this is a good training aid.
Two more points, in my experience the telescope alidade can the average less than 0.2° error taking bearings.
The pencil on the chart is usually that wide.
Another point is when entering port and taking bearings you should use the same equipment that you set this system up with.
Mr. Brown retired from the hydrographic office over 10 years ago then passed away almost 4 years ago.
That's why Bowditch said 1/3, not Brown, 1/3 or 1/2 we are talking an ok, difference as stated in four above the hoizontal bearing change is small.

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