Digital BW, The Print

Hi folks,

I think the issue of workspaces within photoshop and other ICC
compliant applications was/is the single most confusing concept in the
color management process. It is not too difficult to understand that
the scanner/digital camera doesn't see things in exactly the way
monitors display them and printers don't output them quite the way
either of the others "see". No big deal understanding that there must
be a "language translation" between them to make them agree on
anything (as far as it is even possible to get agreement and where we
can't we just sort of guess the closest and go with it).Everyone
understands that English,French,Russian,German etc etc are likely
saying much the same things people universaly say but require
translation to be sure specifically.

It's a different thing entirely when it comes to "work" spaces.
When I first began looking at the technical issues of printing my
photos, I searched all over the net looking for explanations of the
various terms and what they meant and how they worked as a practical
matter. The work space thing seemed to be explained as a commonality
between all the other "hardware" spaces, not to worry, it just
buffered between them but didn't enter into anything else. Not So. It
turned out that some were better than others, some had better Gamut
and offered extended greens or better something else, perhaps more
open shadow values and so on.

What was Not made really clear was the difference between a
"conversion" to a work space and an "assignment" of a work space.
Make a "conversion" and your previously carefully linearized tonal
relationships get shot all to hades. It changes the basic numbers in
your file and, for me at any rate, those numbers "are" the only
commonality. The "assignment" does not alter the base numbers.
It was quite a shock when I first realized what was occuring with
color files when I converted. I at first thought my monitor was going
belly up or needed recalibrated.

It's another challenge to get ahold of the concept of broader/narrower
gamuts. Not because of physical hardware differences. That is easily
understood. Rather it is because we have only 256 levels of each color
to work with and if a file contains the full spread of each it's very
hard to see how anything could be left out when it's sent to the
printer or why anyone would want something left out. The printer
profiles are there to do the translations and force "out of gamut"
nee: unprintable shades to the closest printable color.

I understand where one might want to know what values get "guessed at"
or moved closest to, in your photo so that the file could be edited in
a way to avoid that translation if it would goof things up visually.
That is one of the best things about soft proofing.
I suppose that the different work spaces assist in suppressing some of
this sort of problem. The main problem I see with using some of them
is that while they may be technically absolutely correct in
application, they just don't allow adequately for the human sitting at
the computer who also has a way of "seeing" that is not being truly
translated. I think Clayton expressed this well.

It is lamentable that RGB (12,12,12) and 95+% Black don't simply mean
the same tone is output anywhere, on any device, but that would make
for such a dull world and 'very' dull prints.(g)

Enough-I'll shut up.

Regards
Duane

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Clayton Jones"
<cj@c...> wrote:
> 
> Hello tyler,
> 
> >>Sorry but I really do not think this is correct.  The profile with
> >>which the image is tagged is a fundamental starting point.
> > 
> >Steve, here's the difference (pretty sure). The gamma choice in the
> >Epson driver for BO is not part of the icc data path. It's not a
> >destination space, just a driver adjustment like the other
> adjustments
> >for color when using settings like PhotoRealistic.
> >Therefore, the tagged image space will not be relevant as it's not a
> >space conversion. Anything could probably be assigned and the print
> >would be the same.
> 
> I think you are both right.  BO only comes into play when its output
> time, but an initial color to BW conversion does map the image (if
> that is the correct term) to the default gray workspace.  So the
> initial screen images for DG20 and GG2.2 conversions of the same color
> image, for example, will look identical, but the initial prints will
> be very different (assuming the printer profile is SAS).  However,
> once converted and changed to grayscale, any profile may then be
> assigned to an image, and only the screen image will change, not the
> print (again, assuming the printer profile remains SAS).  Beyond that
> I'm not sure what happens when you check the Black Only box, but your
> description may explain what I've been experiencing. Changing the
> driver gamma setting does change the print. Thanks.
> 
> Regards,
> Clayton
> 
> Info on black and white digital printing at    
> http://www.cjcom.net/digiprnarts.htm