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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
What do stars look like in your eye?
From: Jim Thompson
Date: 2004 Apr 24, 08:55 -0300
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@jimthompson.net www.jimthompson.net Outgoing mail scanned by Norton Antivirus -----------------------------------------