Bruce Woodburn a écrit :

Elevation is not relevant. Marine navigators correct their observations for
their own height above the water (a height difference of 25ft is
significant) but not the height of the tide (which can be 25ft around here).
Think of the Great Lakes as a REALLY high tide. Aviators did not need to
correct for their elevation when using their (bubble horizon) sextants.

Bruce

Hello from Pierre ex captain with french degrees !

Faulse about the corrections : we have to correct for altitude and SPEED too as the
corriolis actions are may be evil in computation depending where and how fast you are :
even the bubble may drift ... in a jet (jet plane such as a Concord !) with a jet (jet
stream at hi alt ..!).

At sea it was also avail some devices as artificial horizons and gyro stabilized ... to be
used in or with sextants (or octants)!
But may be all this is off subject as you are using small units ...

Have fun, I was just passing ... reading ... !

*****************
Pierre BONNARD
http://pierrebonnard.free.fr/index.htm