NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Benefits of Stigmatizing
From: Irv Haworth
Date: 2010 Sep 21, 14:41 -0700
From: Irv Haworth
Date: 2010 Sep 21, 14:41 -0700
Hi Jeremy-Greg. Re your first para. I have a Plath "stigmatizer" on one of my Plath sextants. This device is mounted on a longer version of the shaft which holds the shades . Yes it take a pin point of light from a star and transforms it into a very thin and FAINT line. ( I say faint since it simply takes the initial intensity and spreads it out over a greater area. ) I was never too keen on using it as the line source of light was very faint...anyway it would, in somewhat heavy weather, be of some aid in holding the optics of the sextant at right angles to the horizon. At the time I bought it directly from Plath it was touted as a must have... and not using my gray matter to its fullest but limited extent I did not think about the reduction in intensity. Personally I would not be quick to buy this attachment as an aid to helping one to take a sight. 73 Irv Haworth -----Original Message----- From: navlist-bounce@fer3.com [mailto:navlist-bounce@fer3.com] On Behalf Of Anabasis75@aol.com Sent: Tuesday, September 21, 2010 11:47 AM To: NavList@fer3.com Subject: [NavList] Re: Benefits of Stigmatizing I don't know if we are using the same terms here Greg. When you say a stigmatizer to me, I think of an optical device that transforms pinpoint light sources (stars) to horizontal lines so that they are easier to place on the visible horizon. I have never used one of these, or even seen a sextant so equipped so cannot comment. I don't know how this device can help determine the sextant is vertical unless I am missing something about it. The device on the C&P Horizon Ultra that allows the user to determine if the sextant is vertical they call a "double prism lens" in the Celestaire catalog. I have used this and have never gotten good results with it unless I swung it out of the way. I find the traditional rocking of the sextant to find the nadir or apex of the arc to be easier than the double prism. The other draw back of the dbl prism is the need for a whole horizon glass which many navigators do not favor. Are you talking about one or the other in particular here? What has been your experience with the dbl prism on your C&P? Jeremy In a message dated 9/21/2010 2:37:55 P.M. Eastern Daylight Time, gregrudzinski@yahoo.com writes: Any opinions on the benefits of a stigmatizer when observing stars or planets? It seems that it would primarily help keep the sextant vertical to the horizon during the twilight period. Stigmatizers are not common to most sextants so there must be some draw backs. Greg Rudzinski ---------------------------------------------------------------- NavList message boards and member settings: www.fer3.com/NavList Members may optionally receive posts by email. To cancel email delivery, send a message to NoMail[at]fer3.com ----------------------------------------------------------------