NavList:

Good points, Lu.

"Aluminum has replaced brass as the material of choice for sextants,"
How does it compare for thermal expansion, or rather stability?
Incidentally, the top of the Washingotn Monument is capped with a block of
aluminum, which was at that time the most expensive metal on earth. I wonder if
"engineering resins" or ceramics of some type would have better thermal
stability than metals today? (And still be suitable in other ways.)

"electronics." Splitting one prject into two?<G>

"4. Automatic height-of-eye calculation. "
The sextant would still need to have a manual override, since there are
situations where the user might know what they are standing on, and the sextant
not.<G>

"5. Throw in a little bit of electronic knowledge about the body sighted"
...built-in logging and reduction of sights."

I suppose the question becomes more of, what can be done one-off in a machine
shop, versus what would require custom electronic fabs and that question of
marketing again.

I'd rather just see the simple mechanical exercise, first, to see how a sextant
could be built today. The digital dial readout is available off the shelf
(digital micrometers already do it) so that's just a bolt-on. But that still
shouldn't affect the accuracy of the underlying instrument, readouts would be
trivial to the overall design questions.

"> request for a zoom lens on the telescope."
That's so RETRO.<G> Today there are rifle scopes being made with digital zooms.
That's right, why spend money on complex optics, when you can just use a higher
quality image sensor and tell it to zoom digitally. You can apparently get quite
a nice picture that way if your only goal is filling an eyeball. Also eliminates
the need for filters, although the night-time low-light situation is still
problematic.


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