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    What do stars look like in your eye?
    From: Jim Thompson
    Date: 2004 Apr 24, 08:55 -0300

    I wonder where my right eye's biological optics stand compared to
    experienced sextant-users.
    
    Stars appear to me in my sextant telescope as very slightly fuzzy pinpoints
    of light with a few sharp radiating lines projecting out of them.  The
    effect is less with higher magnification, but still there.  This makes
    finding dead center of the star image a little difficult for me.  What do
    you see?
    
    Venus last night was simply a bigger star-like image.  Frank Reed suggested
    putting the center of Venus on the moon's limb and accounting for SD, but
    there is no way that I could see that with my biological and physical
    optics.  Is that average or bad?
    
    Even with my 6x40 telescope, measuring index error on a fainter star results
    in an imprecision of +/- 0.1-0.3' on successive readings, in part because I
    cannot precisely see where the centers of the two images exactly coincide.
    I usually take about a dozen readings for IE, and always screw the index
    image down to the horizon image.
    
    Jim Thompson
    jim2{at}jimthompson.net
    www.jimthompson.net
    Outgoing mail scanned by Norton Antivirus
    -----------------------------------------
    
    
    

       
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