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    Re: Simex Mariner Polarized Shades...How Well Do They Work/10X Inverting Scope
    From: Alexandre Eremenko
    Date: 2009 Jan 13, 21:56 -0500

    
    
    My esperience with polarized shades (on a Simex
    horizon glass) shows that
    one ordinary operation is impossible with these shades:
    I mean determination of the index error by measuring
    Sun's semidiameter. Unless you have an eyescope filter,
    of course. As I understand, all modern sextants come without
    this filter.
    On the other hand, this method of finding the index error
    seems to me the most accurate and
    most practical of all methods.
    
    Alex.
    
    On Tue, 13 Jan 2009, Mike Burkes wrote:
    
    >
    > Yes, speaking of limited range,the Simex does not lend itself in determining 
    index error via superimposing the Suns(arc set to 0),the index filter having 
    insufficient polarization therefore don't!> From: 
    frankreed{at}HistoricalAtlas.com> To: NavList@fer3.com> Subject: [NavList 
    7021] Re: Simex Mariner Polarized Shades...How Well Do They Work/10X 
    Inverting Scope> Date: Mon, 12 Jan 2009 18:15:10 -0800> > > I agree with 
    Mike. The polarized shades are effective (I have a sextant similar to the 
    Simex) and, as he said, they let you "dial in" a precise amount of shading. 
    They do have a limited overall range, and this can occasionally be a minor 
    nuisance. As for star sights, unless I am mistaken, the polarizers on the 
    Simex can be rotated out of the optical path, just like the shades on other 
    sextants. The 7x35 scope is sufficient for all purposes. If you buy a sextant 
    on ebay with extra scopes that you really don't need, consider selling the 
    scopes separately. They usually fetch a good price.> > -FER> > > 
    _________________________________________________________________
    > Windows Live� Hotmail�: Chat. Store. Share. Do more with mail.
    > http://windowslive.com/howitworks?ocid=TXT_TAGLM_WL_t1_hm_justgotbetter_howitworks_012009
    > >
    >
    
    
    
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