NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Floating mirror
From: Wolfgang Hasper
Date: 2015 Apr 21, 18:04 +0200
From: Wolfgang Hasper
Date: 2015 Apr 21, 18:04 +0200
Hi all,
I considered using water soluble tungsten compound
http://www.heavy-liquid.com/en/productinformation/tableofdensities/
and have a glass-substrate first surface mirror float directly on this liquid.
Assuming the glass carrier is homgenous in density (which I think is justified) this could yield good results.
As yet no idea how expensive that would be.
Regards
Wolfgang
Gesendet: Dienstag, 21. April 2015 um 01:41 Uhr
Von: "Brad Morris" <NoReply_Morris@fer3.com>
An: wolfgang.hasper@web.de
Betreff: [NavList] Re: Floating mirror
Von: "Brad Morris" <NoReply_Morris@fer3.com>
An: wolfgang.hasper@web.de
Betreff: [NavList] Re: Floating mirror
Absolutely agreed Alex. My original estimate was 4 rotations and observations.
For the purposes of illustration, I suggested just 2, making the averaging easier to see.
My initial assessment was that the floating mirror was a bad approach. So called 'common knowledge'. But once Greg pointed out the averaging trick (his point 4), it became obvious that 'common knowledge' was wrong (me included!)
Brad
On Apr 20, 2015 6:52 PM, "Alexandre Eremenko" <NoReply_Eremenko@fer3.com> wrote:
Brad, You wrote: >Assume the mirror has a pitch forward of 5 deg, but only in that angle, side >to side is perfect. I'm afraid you cannot assume that "side to side is perfect". Thus I think you need 4 rotations to average:-) Alex.