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    Re: Compact Lightweight Metal Sextants - Freiberger Yacht vs. Astra IIIB
    From: Bill Morris
    Date: 2012 Aug 11, 15:56 -0700

    "But my main objection is that its micrometer drum is too small and lacks a vernier scale. Even worse, its shinny surface reflects light, making it very difficult to read in many circumstances."

    For those who _must_ have a vernier, it is a simple matter to make one on paper using a computer drafting program, and then to glue it on to the index, followed by a coat of varnish. I attach some examples that can be printed out. Those with unsteady hands get three goes.

    Shine can be removed by rubbing with a piece of emery paper, say 400 grit. Some Freibergers have very respectable arc errors, but I have seen examples having errors of more than 90 seconds, two of them on the bridge of a modern container ship.

    The SNO-T, by the way, is supplied with two 'scopes,a 4 x 40 Galilean and a 6 x 32 Keplerian.

    Bill Morris
    Pukenui
    New Zealand
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