A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Tony Oz
Date: 2021 Jun 4, 08:14 -0700
I missed the time to e-mail you my estimate (I watched the video two or three times), my answer is "32 seconds". On the first run I watched to the boundary color change, when I got the idea, I waited till the spot would get no boundary coloration. Both times it was at the above mentioned moment, 32 sec.
By my guess the instrument consists of two different prisms, one with an even number of reflections, the other with the odd one. They are placed close to one another horizontally, and there is a collecting lens after them.
I'd be really interested to learn the actual construction details! :)