[Leica] Comparing film and digital resolution

[hlritter at bex.net (Howard Ritter)]

As my work schedule slows down towards retirement, I seem to have way too 
much time on my hands. So I decided to pursue a question I?ve been wondering 
about for a long time. I got out some cameras and lenses and a couple rolls 
of film and shot some photos of the house across the pond, scanned the film, 
and cropped down to the small central portion of the images to compare. I?d 
read that the best general-pupose emulsions resolve as high as 150 line 
pairs/mm, which corresponds to 300 pixels/mm, or 7200 x 10800 pixels in a FF 
sensor. That?s around 80 Mpx, which is also in the same range for estimates 
of the information content that I?ve seen quoted for 35mm film. This led me 
to expect that digital would fall short of film, which puzzled me a bit as I 
have been not at all impressed by the technical performance of the slides 
and negs I?ve been scanning.

I picked Fujicolor 200 and Tri-X to compare with the D800, M typ 240, M8, 
and NEX-7, 35mm lenses for the FF cameras, and 24mm for the M8 and NEX-7. I 
also shot the same scene with both the M8 and NEX-7 at 35mm so I could 
compare performance at the same image scale on the sensor.

Suffice it to say that I was surprised by the results, linked below. Sure 
wish I could try Panatomic-X!

 http://gallery.leica-users.org/v/hlritter/Res+Test+Crops/

I was also surprised to discover that even the highest pixel-count FF sensor 
yet available does not match the capabilities of the lenses we use. I?ve 
posted to that effect before, but here are the images to illustrate the 
point.

Comments and corrections of my misconceptions invited & appreciated.

?howard