Digital BW, The Print

Hi Clayton,

>... I'd like to see the same subject taken with a 12mp 
> or greater modern DSLR with equivalent lens.  

I'm interested in DSLR sharpness or resolution also -- not 
necessarily directly comparing to the test Tyler ran, but to the 
issues of how to get the most out of the DSLR systems, as it relates 
to the type of B&W I do.  From my large display landscape 
perspective, resolution was always a significant factor for me.

I've tried for years to have at least some objective criteria.  The 
bottom line for resolution has been 5 pl/mm at display size -- where 
I use 16x20 as the main target.  5 lp/mm is what many believe is the 
approximate limit of our eyes at "normal" viewing distance, but with 
the caveat that edge detection visual systems can distinquish higher 
frequencies.  (The 5D2 is close on paper, so that is part of why I'm 
going there.)

Optics are an obvious variable I've tried to learn something about.  
Most lens reviews are, however, almost useless in predicting the 
level of performance I want.  I've found the MTF curves to be more 
useful, particularly the high resolution (40 lp/mm) tests at 
http://www.photodo.com/products.html (but they're aging). 
 
See also http://www.ocf.berkeley.edu/~ashon/photo/comparo6.htm for a 
convenient colection of Canon lens MTF charts.  These look like what 
Canon publishes on its site, but arranged conveniently.  

Note the definitions of the terms.

Right now, I'm inclined to think that the meridonial MTF performance 
at f8 and at the edge of the frame (18 mm out) may be very 
significant for the performance I'm looking for.

See http://www.paulroark.com/BW-Info/MTF-Canon35f2.jpg and look at 
the meridonial MTF measures.  

So, right now, while I expect film to take my serious wide angle 
business for a while longer, the Canon 35mm f2 is going to be my 
first attempt at getting the most out of the 5D2 on the wide-normal 
side (with 2-fram shots taking me wider).  With the 90 TS, I think 
I'll have my best shot at what I'm looking for.  

I'll let you know if the MTF meridonial measure correlation to 
performance continues to hold.

Paul
www.PaulRoark.com