On Dec 9, 2009, at 11:50 AM, Ken Norton wrote:
<snip>
>> One of the big challenges I've found with a full-digital workflow
>> is when I
> want to do excessive curves and contrast adjustments that I can get
> solarization artifacts as well as a general loss of tonal separation.
Key word "excessive." Photoshop has fantastic tonal controls, the most
obvious of which is curves. Option-Click on the graph and turn it into
a ten-square line. Instand Zone System. Click on a point on the image
you want to mess with, a dot appears on the curve. Etc. And if that
weren't enough, you then have a variety of ways of adjust, or blend,
including Normal, Hue, Saturation and Luminosity. Moving on to actual
Hue & Saturation adjustments, you not only have the macro sliders
everyone is familiar with, but also two color lines down at the bottom
of the box, which have little gray bookends around the actual color
point you're working on. You can move those bookends apart and
"feather" your adjustments into adjacent hues in such a way as to
preserve tonal integrity. And so it goes.
<snip>
> Unfortunately, we're dealing with hard math here. When you have to
> digitize the entire A-D stream with 12-14 bits per pixel, you have
> to reassign the measurements into the final result. When most people
> don't realize is that by the time we've mangled the image into the
> final product that those 12-14 bits per pixel of original A-D
> conversion are now down to an effective 2-4 bits at best. Even less
> if you convert to aRGB as the dynamic range is sacrificed in
> exchange for a wider color gamut.
I convert from RAW into 16-bit ProPhoto. Guess I better stop that, eh?
<g>
> One method I've personally found to deal with this is to mask the
> artifacts
> through random noise injection. The E-1 seems to do this natively,
> but even
> with digitized scans, I'll still have to randomize things to break
> up the
> artifacts if I need to do extensive adjustments. Some may actually
> say that
> this is what defines the "digital look" is the loss of tonal
> separations.
No matter which way you cut it, the E-1 is an antique. And if loss of
tonal separations is a problem, then I'd say the adjustments are
excessive and the original capture is way too flawed to expect
anything worth expecting. I've seen too many huge freaking digital
prints made from digital capture to see loss of tonal separations as a
universal problem. Photoshop's controls are complex, elegant and wide-
ranging.
<snip>
> Specifically in the world of B&W, this is a big issue. When optically
> printing a B&W negative any "curves adjustment" is not only in the
> analog
> realm, but is by it's very nature effectively increasing the "bit-
> depth" of
> the image without loss of tonal separation in the highlights or
> shadows. If,
> for example, I want to increase the exposure (lighten) the shadows
> by 4
> stops in a digital image, you end up with some pretty aweful
> shadows. But if
> I increase the exposure of the shadows by 4 stops in the darkroom
> through
> the dodging process, the shadows lighten but you don't get
> solarization
> artifacts.
Four stops? Lighten shadows four stops? Going from Zone 0 to Zone 4?
Or 2 to 6? Isn't that a bit excessive? Won't your curve look like a
plot of Watkins Glen?
> What is presumed to be an "anti-digital" stance is anything but. I'm
> struggling with both Lightroom and Darkroom technologies and
> techniques like
> everyone else. I doubt there is anybody who has completely "arrived"
> in
> either system. If so, then there wouldn't be any demand for upgrades
> and new
> equipment/software purchases.
Upgrades are the price you pay to keep pace. I don't mind paying, as
long as there's a return. When the returns stop, the upgrades stop,
and I'll cease to care.
--Bob Whitmire
www.bwp33.com
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