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Hey guys,

To clear up any confusion on why you lose exactly one F stop with a 1.4x
converter and exactly 2 F stops with a 2x converter, you have to understand
that this is from the light fall-off (the light has to travel a farther
distance, and falls off as it travels and covers more area) from the
increased distance from the lens to the film plane.  There is
no way to avoid this - it is the Inverse Square Law of light physics.  (2x
example)... As light travels twice as far, it must cover four times the
area, so it's strength diminishes by two F stops.  See my Articles Page on
my web site for more info on the F stops (includes all of the numbers): 
http://www.anet-stl.com/acphotog/home/articles.html

Regards,

Dave Cohen
Photographer, Member ASMP
Action Photographic Webmaster
[EMAIL PROTECTED]
http://www.anet-stl.com/acphotog/home/



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