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   sci.optics      Discussion relating to the science of op      12,750 messages   

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   Message 12,695 of 12,750   
   Lou to All   
   Focal length?   
   02 Nov 23 08:19:01   
   
   From: noelturntive@live.co.uk   
      
   I am short sighted so anything at arms length or beyond is *completely* out of   
   focus.   
   Just noticed though that if I hold a pair of reading glasses ( not mine as I   
   don’t need them for close up vision) at arms length the frame and everything   
   around is out of focus as usual but the image coming through the lens of the   
   background  scene is    
   in complete 20:20 sharp focus .Albeit upside down.   
   Cant quite figure out how this works. Is it something to do with the focal   
   length in my eye between the lens and retina?   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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