Digital BW, The Print

Thanks Tyler and Roy for your insightful postings on the subject of soft
proofing for b&w printing. Here's a further question.

Our fine quadtone (or N-tone) b&w prints are not dead neutral. An
important part of our art is imparting subtle chromatic complexity to
our prints, including, for instance, the "split-tone" prints that many
of us work so hard to create.

As recent happy developments like Roy's QTR and Joe Berndt's IJC/OPM
make sophisticated multi-channel b&w printing accessible to a growing
creative community, I've been wondering what is the best way to
implement a really accurate soft proof in Photoshop. By "really
accurate" in this context, I mean reflecting not just the tonality of
the print but also its subtle colors -- so we can pre-visualize, and
even edit, using all that information. As shorthand, I'll call this a
"Rich B&W Soft Proof" but feel free to correct my terminology if you
like.

Even with a spectrophotometer available, I'm not clear how well our
usual profile-building tools will address this need. I think we are
talking about a workflow in which we edit a monochrome image in
grayscale or "L*" mode (i.e., Lab mode where a* = b* = 0 everywhere)
then printing through a RIP and printer that map this grayscale to a
very-small-gamut color space. Right? 

What's the best way to provide a good preview for this printing process?
It is not quite what ICC Profiles and CMMs are designed to do, is it?
I'm not sure from reading your postings how far you have already gone in
answering this question. What do you think may be the best way to
approach it?

Richard Wolfson
Fine Art Photographer & Digital Imaging Consultant