Re: Snobby Leica

["Peter Jon White" <pjwhite@tiac.net>]

I said,
 If you
> >can't capture the image on film, because of the limitations of
> >grain, what difference does it make?

Erwin Puts replied,

> This is definitely not true. The most recent films (and some older
> ones (Technical Pan) are far superior to almost any lens in
> production. That's the reason why Leica is now in its first major
> optical upgrading since 1979. The new films dictate new optical
> recomputations to take advantage of the image qualities on film. 

Can you substantiate that statement?
> 
> >On a related note, there is a lot of fuss made by some about how
> >wonderful some lens or another is at full aperture.... What good is
> >all that resolving power to anything in the image that doesn't
> >happen to be right on the plane of focus?

> Again not true. If a lens at full aperture is better than another
> one, then the optical qualities will be better till let us say f/5,6
> or f/8,0. After that aperture the levelling off begins. If you focus
> correctly at full aperture there should be no
> 'out-of-focus-problems'. Especially Leica makes sure that the
> optical plane of focus is within very narrow tolerances (1/100mm) to
> the mechanical one, i.e. the negative.

Are you refering to flatness of field here? If you are, that's only 
an issue when the subject is flat, and on a parallel plane to the 
film, (on a camera without tilt and swing).

> The narrow field of depth you
> mention is relative. When shooting at 3 meters with a 90mm at 2,0 or
> 2,8 the depth of field is =B140cm and =B1 50cm, more than enough to
> capture the "thickness" of a human being or a cat.

The only reason that's true is because the film is incapable of 
resolving the difference between sharp focus and the small circles of 
confusion within the range you mention. But the human head is not the 
only subject for a Tele-Elmarit. Depth of field is not an absolute. 
It depends on the magnification. What may appear as acceptable depth 
of field in a 4x5 print may not be at all acceptable in an 8x10.

 A well correced
> lens will not only be exactly sharp at the  plane of focus, but also
> axcceptably sharp before and behind this plane.

How far before and behind the film plane? You make it sound like an 
absolute.

 Again, here is an
> area where Leica is still superior to other lens makers. Erwin Puts
> 
I don't see how Leitz can change the laws of physics. You seem to 
suggest that Leitz lenses have more depth of field than other lenses. 
How is that possible?

Peter Jon White