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    Re: Bubble sextant intervention needed.
    From: Paul Dolkas
    Date: 2012 Oct 18, 23:23 -0700

    Well I'm not, really - but I was always taught that you need to leave a
    sextant out to equilibrate with the outside temp before taking a sighting. I
    have noticed that when I neglect to do this on hot days I get really
    scattered results - which makes sense, since part of it is hot and part
    cold, so the alignment is bound to suffer. Once it equilibrates, it really
    doesn't seem to affect the accuracy, albeit with a smaller bubble size.
    Sometimes though it gets hot enough so that the bubble shrinks to less than
    the solar disk, which makes getting an accurate sighting pretty difficult.
    Maybe I just need to make a nice white quilted sextant cozy, and get the
    best of both worlds...
    -----Original Message-----
    From: navlist-bounce@fer3.com [mailto:navlist-bounce@fer3.com] On
    Behalf Of Geoffrey Kolbe
    Sent: Thursday, October 18, 2012 10:39 PM
    To: NavList@fer3.com
    Subject: [NavList] Re: Bubble sextant intervention needed.
    Paul, I have a stupid question too.
    Why are you leaving your A-12 out in the midday sun?
    When using my A-12 out in the Sahara desert, I did not notice any change in
    bubble size. But the sextant (octant) lived in its box, a yellow foam lined
    Peli case, when it was not actually being used for taking sights. Perhaps
    you just need to paint its box white ;-)

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