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    Re: A guide to AH use
    From: Bill B
    Date: 2014 May 17, 16:02 -0400

    On 5/17/2014 2:41 PM, Norm Goldblatt wrote:
    > Isn't there a cylinder add-on that smears the image horizontally for
    > easier alignment? I thought I read it on this site.
    
    There was an add on for some sextants. They are called astigmatizers,
    and "smear" a point source  into a horizontal line,
    
    Apparently they are no longer manufactured or have fallen into disuse. A
    good overview is to be had in the Navist archives:
    
    http://fer3.com/arc/m2.aspx/Benefits-Stigmatizing-Gebhart-oct-2010-g14092
    

       
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