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    Re: Sextant Comparisons -> to Joel Jacobs...
    From: Courtney Thomas
    Date: 2004 Mar 20, 20:16 -0500

    Thank you Joel.
    
    Are the T and M sextants equivalent in quality ?
    
    Courtney
    
    
    
    Joel Jacobs wrote:
    
    > Hi Courtney,
    >
    > I think it has been explained here before that under the Cyrillic alphabet,
    > the English C is the same as the Russian S so that SNO-T and SNO-T are the
    > same sextant. Your SNO-T sextant has many similarities to the German
    > Freiberger, including its paint, but is appreciably smaller in size. It is a
    > more expensive sextant than the SNO-M. I have seen the SNO-M in both black,
    > and military green.
    >
    > Joel
    >
    >
    > ----- Original Message -----
    > From: "Courtney Thomas" 
    > To: 
    > Sent: Saturday, March 20, 2004 5:39 PM
    > Subject: Re: Sextant Comparisons -> to Joel Jacobs...
    >
    >
    >
    >>Joel,
    >>
    >>I should have said...I have a SNO-M, not T. Anyway, the awful olive
    >>color and the one scope. I got it real cheap and want to bring it up to
    >>snuff.
    >>
    >>I also have a more recent SNO-T which has an agreable silver color and 2
    >>scopes.
    >>
    >>But I obviously agree that the Russian sextants are good and a great buy.
    >>
    >>Appreciatively,
    >>Courtney
    >>
    >>
    >>
    >>Courtney Thomas wrote:
    >>
    >>
    >>>Joel,
    >>>
    >>>I have one and hate the color, but am otherwise satisfied.
    >>>
    >>>What is "black wrinkle paint" ? Where do I get it and how is it applied
    >>>for optimal esthetics ?
    >>>
    >>>Where can I get a proper scope for CELNAV ? How much ?
    >>>
    >>>Appreciatively,
    >>>
    >>>Courtney
    >>>
    >>>
    >>>
    >>>Joel Jacobs wrote:
    >>>
    >>>
    >>>>Fred,
    >>>>
    >>>>Your best bet is a Russian SNO-T sextant. They are very underrated,
    >>>>and have
    >>>>most all the features of the preferred brands, and even come in a
    >>>>
    > smaller
    >
    >>>>size for convenience. However, most of them are sold with only an
    >>>>astronomical scope which presents the image inverted, and IMO are
    >>>>
    > useless
    >
    >>>>for CELNAV. Configured with the 7 x scope, you should be able to buy
    >>>>one for
    >>>>$250.00 because they are a drudge on the market with out an erect
    >>>>
    > imaging
    >
    >>>>scope. You can read about them in detail at:
    >>>>
    >>>>
    >>>>
    > http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3712084763&category=37971
    >
    >>>>&sspagename=STRK%3AMESSE%3AIT&rd=1
    >>>>
    >>>>They wont meet your standards for good looks, but you can get some
    >>>>
    > black
    >
    >>>>wrinkle paint, and make them look as pretty as you like. They are a
    >>>>
    > great
    >
    >>>>buy.
    >>>>
    >>>>Joel Jacobs
    >>>>
    >>>>
    >>>>
    >>>>----- Original Message -----
    >>>>From: "Fred Hebard" 
    >>>>To: 
    >>>>Sent: Saturday, March 20, 2004 12:15 PM
    >>>>Subject: Re: Sextant Comparisons
    >>>>
    >>>>
    >>>>
    >>>>
    >>>>>Doug,
    >>>>>
    >>>>>No, I don't collect older equipment.  I have been trying to acquire a
    >>>>>sextant suitable for lunar observations, so I look for sextants with
    >>>>>defects on Ebay that might still be serviceable.
    >>>>>
    >>>>>I have one British Husun that only has the "star scope."  It's a 2.5x
    >>>>>power scope.  It's my understanding that a more powerful one would
    >>>>>
    > give
    >
    >>>>>more precise readings.  I checked this by buying an old Simex-type
    >>>>>sextant, which subsequently was sold.  I have been looking for another
    >>>>>Husun with the inverting telescope or another instrument.  The Cassens
    >>>>>& Plath was the first that came up which was suitable.
    >>>>>
    >>>>>In comparing the Cassens and Plath to the Husun, I would say, overall,
    >>>>>that I prefer the Husun at this time.  It's prettier, with the
    >>>>>silver-inlayed arc; this increases my fondness for the instrument.
    >>>>>
    > The
    >
    >>>>>black crinkle finish is nicer than the Cassens and Plath's.  All the
    >>>>>screws are varnished or painted brass; there's no aluminum to corrode
    >>>>>with steel screws or react with the brass or bronze (There's no
    >>>>>corrosion on my Cassens and Plath; it doesn't appear ever to have been
    >>>>>used for extended periods).
    >>>>>
    >>>>>The 2.5x scope on the Husun has a very wide field of view, wider than
    >>>>>the 4x "star scope" on the Cassens and Plath.  I have seen no optical
    >>>>>aberrations in the Husun, while the Cassens and Plath star scope has
    >>>>>chromatic aberration, which rather surprised me (reddish fringe on the
    >>>>>bottom of the image and bluish fringe on the top).  The aberration
    >>>>>makes it more difficult to check index error by measuring the sun's
    >>>>>semidiameter.
    >>>>>
    >>>>>The handle on the Husun is straight up and down.  This makes some
    >>>>>lunars easier, whereas the tilted handle on both brands of Plaths,
    >>>>>while it makes looking at the horizon easier on the wrist, makes
    >>>>>
    > lunars
    >
    >>>>>more difficult.  When holding the instrument between shots or while
    >>>>>waiting, the Husun is less fatiguing to hold
    >>>>>
    >>>>>The star scope on the Husun is in close to the horizon mirror.  This
    >>>>>centers weight in the instrument, making it less fatiguing to hold.
    >>>>>Being close in to the horizon mirror, the smaller mirror does not
    >>>>>restrict the field of view of the instrument as much as one might
    >>>>>suppose.  I suppose the larger mirrors would be "faster" optically,
    >>>>>however.
    >>>>>
    >>>>>The perceived weight of the two instruments is similar.  I have not
    >>>>>actually weighed them.
    >>>>>
    >>>>>The lamp on the Husun can be swung around to illuminate my wrist band
    >>>>>when recording data.  The lamp on the Cassens and Plath is guided to
    >>>>>illuminate the scales only, making recording data more difficult.
    >>>>>
    >>>>>The box on the Husun is significantly smaller than the box on the
    >>>>>
    > other
    >
    >>>>>instruments.
    >>>>>
    >>>>>These are my impressions after two days.
    >>>>>
    >>>>>Fred
    >>>>>
    >>>>------------------------------------------------------------------------
    >>>>
    >>>>>Frederick V. Hebard, PhD                      Email:
    >>>>>
    > mailto:Fred{at}acf.org
    >
    >>>>>Staff Pathologist, Meadowview Research Farms  Web: http://www.acf.org
    >>>>>American Chestnut Foundation                  Phone: (276) 944-4631
    >>>>>14005 Glenbrook Ave.                          Fax: (276) 944-0934
    >>>>>Meadowview, VA 24361
    >>>>>
    >>>>>On Mar 19, 2004, at 5:44 PM, Royer, Doug wrote:
    >>>>>
    >>>>>
    >>>>>
    >>>>>>By the way,do you collect older sextants?Don't you also have some
    >>>>>>
    > older
    >
    >>>>>>British equipment you wrote about in the past?Just curious.
    >>>>>>
    >>>>>>
    >>>
    >>>--
    >>>Courtney Thomas
    >>>s/v Mutiny
    >>>lying Oriental, NC
    >>>WDB5619
    >>>
    >>>
    >>
    >>--
    >>Courtney Thomas
    >>s/v Mutiny
    >>lying Oriental, NC
    >>WDB5619
    >>
    >
    
    
    --
    Courtney Thomas
    s/v Mutiny
    lying Oriental, NC
    WDB5619
    
    
    

       
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