Originally Posted by DREW WILEY
It's not bullshit. I am aware of the other factors and that the idea of sharpnes is a subjective one to begin with. Those numbers are a useful means to understanding why color slides or negatives may appear to have less resolved detail than black and white films. I used to shoot Kodachrome long ago and was disappointed when I scanned them a couple years ago on an Imacon scanner and found their resolved details were
No match for most of my Black and white negatives. There is something to the fact that light has to travel to three layers, not counting the filter layer in color film. The MTF is useful for understanding the maximum capabilities of a film like we may know a digital cameras resolution, of course the lens resolving on that film determines how much can be revealed. There is no number crunching at all, just simple comparing of numbers to try to understand some of the different properties.
Acutance of the film during processing is different than the actual resolved detail as it can alter the contrast between resolved details and the perception of sharpness can be very high. If the details are not recorded however, no amount of processing can create them, which is why I mentioned this problem of resolution/sharpness arises mostly from printing very large or scanning very high resolution and realizing the film doesn't have incredible detail after a certain size. Of course you don't take the numbers to heart and say "well crap, I'll never shoot color again now" because that's just stupid.