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    Re: ebay "reproduction"
    From: Frank Reed
    Date: 2013 Jan 9, 11:59 -0800

    Dave,

    I wouldn't really consider it cheap at that price. That's $110 plus $40 for shipping from India. And all that for a reproduction? You can get a used Davis plastic sextant for considerably less, and it would actually work.

    But it's an interesting product anyway, a new "wrinkle" in this buyer-beware market. There have been "antiquey" looking reproductions on ebay for years, but this is the first I've seen that's modeled on a sextant that's still in production (it looks just like an Astra IIIB). Although it could certainly measure angles since it is optically an actual instrument of reflection, the biggest uncertainty is the micrometer. It may not even turn properly. I would expect you could measure angles to half a degree with no difficulty though it may have substantial arc error (you make a table of that, then it's correctable). It has all the adjustment screws in the right places, but they may not do anything. This "sextant" might be usable for piloting, but I think it's highly unlikely it could be made usable for celestial navigation. In other reproductions I've seen, a major problem is that the shades are just lightly colored glass. They're nowhere near sufficient for Sun sights. And that seems to be the case here, too. In one of the photos, we're looking through all three index shades and the index mirror is still clearly visible through them. That's no good.

    -FER


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