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    Theodolite Shots at Night [was Long Range Desert Group]
    From: Brian Whatcott
    Date: 2002 Feb 3, 10:58 -0600

    I found this post from Paul Hirose valuable.  This is indeed a
    pleasure of  using interest group lists.
    Thanks
    Brian W
    
    He wrote
    
           illuminating [theodolite] cross hairs.
    
    
    >One old surveyor's trick for making Polaris observations at night is
    >to hold a flashlight just outside the field of view and shine it into
    >the telescope objective lens.
    >
    >You can also place the tip of your index finger, illuminated by a
    >flashlight held in the same hand, so it protrudes into the field of
    >view. I like this method a little more, but either one is quite
    >effective for making the reticle visible without washing out the star.
    >
    >Many theodolites have a small "lollipop" in the telescope, easily
    >visible through the objective lens. It's made of thin metal and is
    >normally turned edgewise. For crosshair illumination, you turn the
    >lollipop 45 degrees. That causes its round tip, at the center of the
    >telescope tube, to intercept a light beam supplied through the side of
    >the tube and deflect it back toward the reticle. The light comes from
    >the circle illumination optics, so the lamp and power source need to
    >be operating. Or you shine a flashlight into the illumination port.
    >...
    >paulhirose---.net (Paul Hirose)
    
    Brian Whatcott
       Altus OK                      Eureka!
    
    
    

       
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