NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: re posts on buying a sextant
From: Jeremy C
Date: 2011 Apr 8, 17:30 -0400
From: Jeremy C
Date: 2011 Apr 8, 17:30 -0400
C&P seems to still be going strong. I was just looking at
their online catalog yesterday. http://www.cassens-plath.de/index.php?id=18
They are more into magnetic and other style compasses, but still make sextants
as well.
My C&P bought a couple years ago now was made a few weeks before I
received it, so I am pretty sure that their production runs are pretty small and
infrequent.
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As for buying a sextant. I would first look at your goals and
financial position.
If you are just interested in getting some readings to play with
mathematics and aren't interested in maximum precision, then a nice Davis
plastic sextant might do the trick. Likewise, if you are not sure if you
are going to like CelNav, this might also be the way to go since they are
relatively inexpensive.
If you are a CelNav hobbyist and are interested in shooting lunars and
really refining your skills, I would suggest a metal sextant. The Astra
IIIb is a good choice for this if the budget is lacking, and any of the other
makes are great if you have slightly looser purse strings. Ebay finds
will also be a good choice for the hobbyist, but caveat emptor, since any damage
will be hard to notice by an ignorant seller and may be difficult and/or
expensive to repair.
If you are navigating a vessel of any size on the oceans and will need
to actually use the LOP's then I would strongly suggest getting a new, metal
sextant. You won't have to worry about prior abuse and you can be certain
that the positions will be free from practical error. Any of the current
brands will be suitable for this purpose.
Once you have made the major choices of metal or plastic and new and used,
you have to decide what quality and features you want on your
sextant.
For me it was all about the polarizing shades on the C&P Horizon
Ultra. I love them, and was willing to pay for them. In addition, I
like high magnification scopes, so the 7x35 went in the box as well as a bottle
of lubricating oil.
On small boats a lower powered scope is better. 3-4x is probably
best. For lunars or on stable platforms (land and ships), I'd suggest a
6-7x scope.
For land based sextant users, I'd suggest either a bubble horizon
attachment or artificial horizon to make inland use possible.
If you want to get fancy, a 5x data-scope can be added as well as an
astigmatizer but these are pretty low down on the list of accessories.
There is much debate on the type of horizon mirror. The whole horizon
mirror is easier to use, especially with lower power scopes, but you can
loose the horizon at the edge of twilight. Traditional half-mirrored
glasses are better at the edge of twilight, but get annoying when trying to
rock the body on the horizon, or finding a star in rough seas. The best of
both worlds can be had with a traditional mirror and high powered (7x) scope,
but these are hard to use on small boats. I have used both kinds
extensively and much prefer the whole horizon with a 4x scope and the
traditional with a 7x scope. If I had to choose between one or the other,
I'd choose a whole horizon mirror for ease of use despite it's
limitations.
Jeremy