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    Re: Eyesight dangers using telescopes was: [8760] Basics of computing sunrise/sunset
    From: Douglas Denny
    Date: 2009 Jun 25, 13:16 -0700

    Important correction to make clear before confusion reigns:
    
    The exit pupil of an astronomical telescope is the image size of the objective
    lens itself which forms the aperture stop.
    
    
    Should read:-
    
    The exit pupil of an astronomical telescope is the image size of the objective
    lens itself BY THE EYEPIECE  - which forms the aperture stop.
    
    
    Douglas Denny.
    
    
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