[Leica] performance stopped down

[Erwin Puts <imxputs@knoware.nl>]

Alex wrote in part:
"Mark - unfortunately you've missed Erwin's point.
"All lenses are 'better'' stopped down' than wide-open.

Well that is not my point.
There are Leica lenses which improve markedly when stopping down to 
f8, such as the older 1.4/35.
There  are Leica lenses that do hardly improve on stopping down as 
the 2.8/24 ASPH or the 3,4.135 APO. These lenses are wide open as 
good as stopped down one or two stops. These lenses actually has less 
good performance at f8.
There are lenses who do not improve when stopping down. like the 
R-2,8/180 APO and R 4/280 APO, They  also degrade afer f/8.
So many current Leica lenses are wide open as good as stopped down 
two stops. So the statement :"all lenses are better stopped down than 
wide open" is too broad to be true.  There are lense that when 
stopping down do not improve or actually degrade.


Erwin