NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Hybrid artificial horizon
From: Peter Monta
Date: 2020 Jul 25, 10:48 -0700
From: Peter Monta
Date: 2020 Jul 25, 10:48 -0700
Hi Greg,
Attached are a pair of sun images looking each way across a floated first surface mirror in a Davis artificial horizon. Am I to line up all the images to trim float to even keel ?
Yep. The first image looks like about 20 arcminutes; is that in the ballpark of what you normally see when differencing your two observations rather than averaging? What puzzles me a little is that the second image looks a little different, more like 10 or 15 arcminutes. Would you be trimming the keel by nibbling off bits of styrofoam?
By the way, those "comet tails" I also saw. I guess they're a result of getting close to the borders of the puddle, where the curvature of the water starts to make things wildly astigmatic. It's useful for centering, because one can translate left/right/up/down, watching for comet tails and staying in the sweet spot.
I'll have to try the floating mirror at some point. Using a plain dry mirror surface is certainly a plus for the floating mirror, though in the case of puddles one can try using the dry mirror corners if there's enough real estate.
Cheers,
Peter
