>
> I'm the first to say I know nothing about B&W films, so I don't know the
> cause, but several images came out with upper mid tones pushed up into
> the highlight area. In others, the tonal palette and graduations seem
> excellent to me. Fortunately, whatever the cause(s), exposure,
> development or scanning, the high end was just squashed up near the top,
> not clipped, so they can be adjusted.
>
I believe that what you are seeing is one of the odd characteristics of
scanning instead of optical printing. For lack of a better way of explaining
it, the "gamma" of the film is optimized to match the "gamma" of the paper.
When you scan the film, the gamma is off for screen viewing.
On the flip side, I find that a couple of the chromogenic films (T400CN
specifically) scans better than they optical print. The only way I can get
T400CN's gamma to match the paper is through split-grade printing.
I've fought this very thing unendedly. Getting a good scan from B&W film is
a miserable affair. Getting good tonalities in an optical print is far, far
easier. I believe that both Dawid and I agree that the best way to digitize
a B&W film image is to optically print it then digitize the print. The
"interprint" doesn't need to be final display quality, in fact, it can be a
little on the flat side, but the optical printing process gets the "gamma"
to match properly and the tonal assignments correct in relationship to each
other. Another reason to use the chemical "interprint" is for the grain. The
aliasing that occures during the scanning process greatly accentuates the
grain. Depending on contrast-grade, a 6x9" (image area) print from a 35mm
roll of Delta 400 pushed one stop is nearly grainless in an optical print.
But when the negative is scanned, the grain looks like golf-balls. If you
scan the optical print and apply a touch of NR, the resulting image can be
completely grain free.
Chris Crawford has managed to find some way to digitize negs, but he has
probably modified his film development to optimize it for scanning, not
optical printing. My negs are optimized for optical printing. Based on what
I see with Nathan's on-screen film images, I'm going to guess that his
development is also optimized for optical printing.
AG
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