NavList:

Attached is my 1hr+ crack at Ho from Hs for the Moon, which I leave for others to check.  It does appear to tie in with a 60 second check in the Air Almanac.  Presumably if you were taking several shots every day certain calculations would become reusable all day, or night.  To summarise, I got:

Ho=Ha – R + P in A +/- SD
Ho=18° 53.90’ – 3.00’ + 57.04’ – 16.45’ = 19° 31.5’

If using a Bubble sextant dip would be zero.  SD wouldn’t matter if you placed the Moon in the middle of the bubble.  With accuracy you might expect with a bubble sextant you could ignore OB and f, but you would certainly need basic Ro and P in A.  Incidentally, if your peri-sextant turned out to have a pendulous reference graticule rather than a bubble, you might try touching the Moon’s UL or LL against the horizon line of your graticule and subtracting or adding SD.  I’ve not tried it, but I’ve heard of it being done.  I’ll try it next time I look at the Moon.

For 1’ level accuracy, you could probably: use Ro and neglect f; neglect OB; and use an average SD for the Moon on most occasions.  A sift through the Daily Pages of the NA or AA might reveal occasions when the Moon is off limits and why.  Failing that we were always taught to treat any Hs less than 15d with suspicion, because refraction is so difficult to tie down accurately. Identifying a UL or LL of a crescent Moon might also be a problem. DaveP

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