Re: button-hole problem

Hi Laurence F., and Luiz

Laurence wrote: [Sat, 23 Apr 2005 13:40:11 +0200 (MEST)]

 > On Sat, 23 Apr 2005, L. Nobre G. wrote: 
 >
 >> >From the experimental physicist point of view the perspective projection
 >> of a circle on a plane is "allways" an ellipse.
 >> But
 >> the projection of the center of the circle is "not" the center of the
 >> ellipse.
 >
 >How can this be reconciled with what Laurent S. and Peter have written?
 >Again, in words of one syllable, if possible, please.

No way! 

Now a polysyllabic clarification.  Hyperbolic images are common
visible and computable.  Hundreds of millions of automobilists
including most physicists see such hyperbolas on the road when using
their high beam headlights at night. Hundreds of millions of
citizens see such hyperbolas on the wall of a room at night above a
round lampshade.

But the statement about centers is OK.

Cheers

Laurent S.