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    Re: LED Street Lights
    From: Paul Hirose
    Date: 2017 Aug 26, 09:38 -0700

    On 2017-08-25 16:33, David C wrote:
    > It will be my birthday soon and when I am asked what I want I may say "a 
    reconditioned A12 from Celestaire".
    > But I have a problem. I live in an area with light pollution.
    
    I found the A12 difficult (but not impossible) to use for star shots in
    a light polluted area, due to the bubble illumination system. It shows
    the bubble as a dark circle against a lighted background. However, the
    latter also washes out the star.
    
    Another problem is batteries. Apparently dry cells in the 1940s were a
    little smaller in diameter. I had to laboriously strip the jackets from
    modern batteries to get them to fit.
    
    The viewing position for star shots is not the best, as you must hold
    the sextant above eye level and look up through it. On the other hand,
    the A12 is comfortable for sun shots since it's held at chest height and
    you gaze down into it.
    
    I still have the A12, as well as a periscopic bubble sextant. But I
    haven't used either in several years. A marine sextant (sans artificial
    horizon) is much more fun.
    

       
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