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    Re: Observator Mark 4 Sextant
    From: R B Emerson
    Date: 2008 Aug 14, 09:27 -0400
    I stand corrected on the issue of the separate filters for the index and horizon.  I wish "andrejsv", the winning bidder, joy of his new sextant.  :-)

    Out of curiousity, I tried a search for Observator sextants on eBay and turned up another Observator sextant, albeit in a more traditional form, offered by an Indian company involved in ship breaking (or at least that's their story and they're sticking to it).  Search for "sextant observator" to find this auction. 

    Rick Emerson
    S/V One With The Wind

    engineer wrote:
    Members can read the original patent document at
    http://v3.espacenet.com/origdoc?DB=EPODOC&IDX=EP0082556&F=0&QPN=EP0082556.
    
    Its claim to originality are that the filters are contained safely
    within the viewing means and that they can be made of cheap material
    like photographic film, as they do not have to have flat parallel
    faces, lying as they do behind the objective lens of a Galilean
    telescope. The index beam and the horizon beam do in fact have
    separate filters which do not get "filthy" like ordinary ones, nor do
    they invited destruction at the hands of the clumsy. The filter
    density can be made continuously variable.
    
    Bill Morris
    
    On Aug 14, 9:25 am, "Richard B. Emerson" <pavil...@pinefields.com>
    wrote:
      
    I've never seen this sextant before but I looked over the eBay auction
    and decided it has one big problem: filters.  As best I can tell there's
    no way to use one level of filtering for the index mirror and another
    for the horizon.  Things like a bubble horizon are out (unless one's
    built in?) as are astigmatizers and varying scope powers.  Of course,
    all off that could be built in.  But I'm not holding my breath on any of
    that being present.  Good luck with your bidding!  :-)
    
    Rick Emerson
    S/V One With The Wind
    
    
    
    Greg Rudzinski wrote:
        
         Has anyone on the list used an Obervator Mark 4 sextant (Dutch
    made) and how does it compare to other sextants ? There is one listed
    on Ebay right now.
          
    Greg- Hide quoted text -
          
    - Show quoted text -
        
    
    
    
      

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