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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Can You Bias Ho?
From: Peter Monta
Date: 2014 Apr 2, 13:39 -0700
Small pentaprisms can be had for pretty cheap from places like Surplus Shed (e.g. a 14 mm prism for $10; link below) or eBay. Any deviation error from 90 degrees can be treated like an index error and measured in situ.
http://www.surplusshed.com/pages/item/l13726.html
By the way, here's a better link to Nicolàs de Hilster's page on the pentaprism attachment. A full set of photos and drawings. Nice!
From: Peter Monta
Date: 2014 Apr 2, 13:39 -0700
Hi Brad,
I think in actual use it would look like the attached drawing. It seems a reasonably comfortable position for the sextant.http://www.surplusshed.com/pages/item/l13726.html
File:
