NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Bris accuracy?
From: Alexandre Eremenko
Date: 2004 Nov 8, 14:03 -0500
From: Alexandre Eremenko
Date: 2004 Nov 8, 14:03 -0500
This is amazing! It seems to be in the same precision class as the best brass sextants. Did you use the natural horizon? As I understand it measures only some discrete pre-assinged set of possible altitudes, so you have to wait and only to record the time when such pre-assigned altitude is reached. How frequently this happens? I mean how long you have to wait in the average? Or, which is the same, what is the typidal difference between these pre-assigned apltitude values? Alex. On Mon, 8 Nov 2004, Royer, Doug wrote: > Here are some results from last Sat. (11-06-04) and Sun. (11-07-04) > positions useing the Bris. 3 differant alts of the Sun taken at 3 differant > times of day from the same terrestial position.No averaging used as when the > image of the Sun is where it needs to be(on the Bris) as according to the > user instructions the time is noted and each sight is reduced to find the > LOP. > Both days the position by GPS coordinates: > 32* 49' 24" N > 116* 49' 49" W > > 11-06-04 most probable position.2 alts and times during the morning hrs and > 1 alt and time during the late afternoon hrs: > 32* 49' 31" N > 116* 50' 07" W > This is between 600 - 650 yds differance at a bearing of 288* T from the GPS > pos. > > 11-07-04 most probable position. 1 alt and time in the morning hrs and 2 > alts and times during the later afternoon hrs: > 32* 49' 36" N > 116* 49' 43' W > This is between 400 - 500 yds differance at a bearing of 012* T from the GPS > pos. > > This is only the 4th weekend I've had to play with this instument and the > "accuracy" of the MPP is getting better the more I use the instrument.