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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Watching a star for IE: an obturator trick?
From: Tony Oz
Date: 2019 Dec 8, 09:53 -0800
From: Tony Oz
Date: 2019 Dec 8, 09:53 -0800
Hello!
The ongoing discussion of the star-to-star angle as the sextant sanity check has reminded me my efforts to eliminate the IE (and side error too).
For me it is not so easy - even with the 7x (Keplerian) scope - to tell if both images of a star coincide perfectly. I have to move the index arm slightly to see where each image is.
Last time I did the adjustments I asked a friend to move his palm infront the horizon and index mirrors thus blocking temporarily either of the view paths. With the images (alternatively) blinking I can see the [non]coincidence much more clearly. I think some sort of fan propeller could be used as an obturator. Will try next time I take my sextants to the shore.
Please comment.
Warm regards,
Tony
60°N 30°E
