NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Advice on Sextant
From: James N Wilson
Date: 2009 Aug 3, 16:46 -0700
From: James N Wilson
Date: 2009 Aug 3, 16:46 -0700
Peter: I give out the following to my students from my learning about various sextants to help them choose. Jim Wilson J. N. Wilson, SN Balboa THE SEXTANT -- as seen by the small boat sailor Size -- small ones stow easily -- accuracy O.K. Telescope -- less than 4 power; 2x to 3x recommended: 6-7X -- NO! -- 12X?? - remove in rough seas - big objective lens for lots of light Horizon Glass -- half clear, half silvered; not cut off at edge of mirror - large -- big round ones better (disadvantage of small sextant) - half silvered -- sometimes difficult to see horizon Vernier on micrometer drum -- not required - accuracy doesn't warrant - can lead to reading errors Shades -- all O.K. -- polarized may be easier or quicker Feel -- weight, ease of movement, etc. -- try it! - weight -- some heavy, [steadier] -- some light, [less fatigue] - personal preferences govern Built-in Light -- very handy, can be used to illuminate forms and watch Bubble Sextant -- no good for sights from boat - O.K. with natural horizon Astigmatizer -- I don't use - hard to hold body in field Plastic -- O.K., good spare -- accuracy questionable, but probably O.K. Fine points - shade interference with field - drum not pinned to shaft ____________________________________________________________ Be more successful with these great CRM solutions. Click now! --~--~---------~--~----~------------~-------~--~----~ NavList message boards: www.fer3.com/arc Or post by email to: NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---