NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Dip Anomaly
From: Ken Gebhart
Date: 2008 Mar 13, 21:57 -0500
From: Ken Gebhart
Date: 2008 Mar 13, 21:57 -0500
I would think so. First, I assume you are on land with the sextant propped up, and not hand held. Next, the horizon should be sighted with the top of the bubble, then the bottom of the bubble, and the readings averaged, and finally the sextant must be calibrated for accuracy. The latter can be done with a star in the same manner. My experience with bubble sextants is that repeatable readings can be obtained within 20 to 30 seconds of arc. Ken Gebhart On Mar 13, 2008, at 3:22 PM, Greg Rudzinski wrote: > > Question for NAVLIST: Can a bubble sextant be used to measure dip > anomalies from a known height of eye? This would be a negative > measurement in minutes from bubble to horizon. > > > --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
