Next message: Ken Muldrew: "Re: Taking the mirror out of the equation"
Bill you wrote:
"My Astra III B (circa 2005) has a pair of shades
(index and horizon) that transmit so little I cannot make out the sun in
June at 40N. I can only surmise that if the sun has a declination similar
to my latitude in January, it will be of more use than some other shade
combination. "
The Sun is only a tiny bit brighter when it's straight up, so I think we
have to face up to the same explanation as for that M.A.C. sextant: bad design
(or bad execution of good design by the manufacturer). I have an Astra III B
(brand new and never used, but maybe ten years old --ebay again) and all the
shades make sense.
-FER
42.0N 87.7W, or 41.4N 72.1W.
www.HistoricalAtlas.com/lunars
