dear Dan
the wristwatch as compass has 3 problems:
a) it shows the time of a different longitude, the one of the time-zone
(GMT or DST).
You should correct it for the local time but it is possible only if you
know your longitude.
b) you should correct the time also for eot, it means you should start
with the local Sun time for the longitude where you'll use it.
You can admit a little bit of imprecision avoiding a) and b), if your
longitude is not so far from the one of the time-zone.
c) you have to rotate the watch around the 3-9 axes of the colatitude
angle, so you have to evaulate also your latitude.
Overall it isn't a reliable way to find the north, it is useful to have
a rough estimate if you haven't other instruments.
I have some 3D drawings for a book I'm writing, I attach 2 images, if
you wish I can send you, or anyone who request them, a more defined jpg.
ciao Fabio
--
Fabio Savian
[email protected]
www.nonvedolora.eu
Paderno Dugnano, Milano, Italy
45° 34' 9'' N, 9° 9' 54'' E, UTC +1 (DST +2)
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