NavList:

Bill,

> Local time 12 Average of 5 obs. error 0.0' (sigma=1.5')
> Local time 12:40 Average of 6,  error 0.0' (sigma=1.0')

You picked the two best series I reported
Notice that sigma is 1'  and 1.5' which characterizes the
accuracy of one observation. This is fine for THIS sextant,
of course, because the scale reads only to 1',
but from a GOOD full size sextant I will expect sigma=0.2'
or 0.3'. (In fact I consistently achieve sigma=0.3'
with SNO, but the misterious systematic error of this SNO
shows that it is not so good).

It's true, I also reported a Lunar which was practically
perfect (ONE observation, without scope!)
But of course, this was a coincidence.

Yesterday I shot a lunar from the shore, Sun-Moon, 7 shots,
at 77 degrees, and the error of the average was 1.1'.
(The maximal error of ONE observation was 1.5')
Again, not so terribly bad for THIS sextant, but of course VERY BAD
for a Lunar. This kind of sextant was certainly not designed for
taking lunars.

Alex.


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