Originally Posted by nuru05
Nuru05 [and any other potential users of a Davis plastic sextant]:
Davis sextants are perfectly usable for celestial navigation
across oceans. However
, keep in mind that you will need to check the index error very
often. (At least
after each round of sights. Preferably before and after each individual sight.) These sextants are extremely sensitive to temperature changes, causing the index error to fluctuate quite a bit. Allowing the sextant to acclimate to the outside temperature before using it will help some (as it does with all sextants), but you will still need to check the index error often. When using mine, I even noticed that the index error would change based on how tightly I held the handle.
Also, if you do end up buying
colemj's sextant, you will probably want to turn the scope
around the right way before trying to use it.