NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Brad Morris
Date: 2013 Dec 16, 21:34 -0500
Hello Herbert
The reason is quite simple. Two fuzzy blobs (stars in my scope) pass thru each other. Move the index arm by an arc minute, they still 'pass thru each other'. Move it back the other way two arc minutes. The blobs pass thru each other.
Rather than distinct points, stars are fuzzy blobs. If your objective is to calibrate to the nearest arc minute (or so), then perhaps the star to star distance may work for you. I, on the other hand, was looking to calibrate to the tenth of an arc minute (or less).
In private discussions with Alex and Frank, we agreed that using the lunar distance sight would provide a crisper edge to edge arrangement, making it much more suitable for arc calibration.
Brad
Brad,
You wrote:
"I was under the mistaken impression that star to star distances could be used to calibrate the arc. I have since been thoroughly convinced otherwise."
In a nutshell = why?
Herbert Prinz
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