From: UCLAN@invalid.net   
      
   On 1/11/2015 6:25 AM, Phil Hobbs wrote:   
      
   > All concave mirrors do that, but at a different distance for different   
   > curvatures. The point where the image becomes large and then flips over is   
   > the focal point. It's located halfway between the mirror surface and the   
   > centre of the sphere. (A spherical surface like your mirror can be looked at   
   > as a section cut from a full sphere.)   
   >   
   > The new mirror is more deeply curved than the old one, which gives it a   
   > shorter focal length.  There isn't much you can do about that except get a   
   > shallower mirror.   
   >   
   > Cheers   
   >   
   > Phil Hobbs   
      
   Thanks for the explanation. I was puzzled by why the old 4" mirror could   
   be 2' or more away from the object with no image inversion or distortion   
   taking place.   
      
   This will make it *extremely* difficult to buy a satisfactory mirror online.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)