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

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   Message 11,076 of 12,750   
   glen herrmannsfeldt to Jos Bergervoet   
   Re: IR goggles   
   11 Feb 12 21:20:10   
   
   XPost: sci.physics, sci.physics.electromag   
   From: gah@ugcs.caltech.edu   
      
   In sci.physics.electromag Jos Bergervoet  wrote:   
   > On 2/11/2012 2:21 AM, RLW wrote:   
   >> On Fri, 10 Feb 2012 00:03:55 -0800, anorton wrote:   
      
   >>> Actually, Peter, the surface of the moon appears no brighter   
   >>> in any telescope than it does to the naked eye.   
      
   >> In fact, it does.   
      
   > No it does not. Run a Web search for "exit pupil" (your own advise..)   
      
   I believe that 'appears' is important above. How bright something   
   appears depends in some sense on the average over the whole   
   field of view, and some on the peak. Even more, it could depend   
   on which part of the eye it was on.   
      
   Next, can you explain why the moon looks bigger near the horizon   
   than when it is high in the sky? It is easy to show that the   
   angular size is the same in both cases, but subjectively the   
   size is different.   
      
   -- glen   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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