Seems to me that Depth Of Field depends on the width of the front lens, so for
the same light
gathering ability, is less with a mirror lens because of the middle blockage.
Even with a diaphragm, the DOF could not be less than what you would calculate
for the width of
the internal blockage, the secondary mirror.
tOM
--
tOM Trottier, Ottawa, Canada
758 Albert St, Ottawa ON Canada K1R 7V8
+1 613 231-6115 N45.41235 W75.71345
http://groups.yahoo.com/group/ottawa-photo-clubs
"The moment one gives close attention to anything,
even a blade of grass, it becomes a mysterious,
awesome, indescribably magnificent world in itself "
-- Henry Miller, 1891-1980
==============================================
List usage info: http://www.zuikoholic.com
List nannies: olympusadmin@xxxxxxxxxx
==============================================
|