P3D Re: Sharpness Anxiety

[jacob@xxxxxxxxxxxxxx (Gabriel Jacob)]

With Tom Deering's recent post about lens testing and Dr.T's 
post about peoples overly concern about about lens sharpness,
it makes me wonder....

Dr.T writes:
>I have been puzzled by statements that camera or lens A is better
>than B.  I have tried Realist 2.8's, 3.5's, Belplascas, Ektar lenses,
>Kodaks, etc.  I don't see any differences worth worrying about,
>especially under normal shooting conditions (usually at f8 or f11).

How about at f5.6 and lower? I remember reading that most are
not quite up to par at wider apertures, especially of course with
3.5's. But I have also read about poor quality control, with not
all 3.5's or 2.8's created equal. And this is more within the
same make of camera, rather than between different camera makers.
This was expained away because of the lax quality control in the
50's. 

Finally for the lens experts..., long ago I thought "faster"
lenses were a rip-off because they just took the same lens
and put a larger diaphragm, and charged a bundle. Obviously or
not so obviously this is not the case. Okay, I do know that the 
f-numbers are related to the diameter of the aperture and to
the focal length of the lens. But how do they classify the 
lenses into 3.5's and 2.8's? Do they make a single batch and
sort them into different 2.8's and 3.5's or are they really
made differently!?!
 
Gabriel 



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