[Leica] Performance Limits

[barney@sgi50.wwb.noaa.gov (Barney Quinn)]

Hi,

I have been reading with as much understanding as I can bring to them
Erwin's wonderful explanations about the diffraction limits of
lenses. I'm in awe of what he knows. His posts got me thinking, and
make me want to share a bit about my experience with my new M6, and
then to recast a question about quality in terms of end-to-end system
performance.

I use TMAX 400CN in my M6. The lab which does my developing and
printing makes me 11X14 enlargements on Illford Multigrade IV
paper. What really matters to me is how the final print looks. The
results which I get using my 50mm f2 black summicron are hard to tell from
the 11x14's made with my designer label 6x6 system using conventional
ISO 100 silver based B&W film. I also have what I think is a pre-WWII
90mm F4 uncoated Elmar which gives results which are more than
acceptable.

I'm quite happy about this. Clearly I have bought into the
conventional wisdom which has lead me to underestimate the quality of
my Leica while expecting too much from my MF rig. This leads me to a
question for Erwin, and the group. What, and where, for a simple
minded engineer like myself, are the limits and real world constraints
on the performance of a photographic system. 

Barney