Digital BW, The Print

I think two very different issues are getting bundled into this one topic.
The differences between them are very important to understand. The first is
whether having a good monitor profile (and proper colour management
settings) is important or not.  The second is the fact that the print space
is very different from the displayed workspace.  I regard the first as
important and would urge that what I would call "dumbing down" the monitor -
deliberately moving it away from a well-profiled state - is not a wise
course of action, particularly if it results from a lack of understanding of
the second. 

But the biggest issue in this discussion is that the print space is a lot
narrower than the displayed workspace.  We can display better black and
brighter white than we can print - on a well-profiled monitor or not so
well-profiled.  Understanding this is useful.  How the workspace and print
space map to each other are quantifiable - at least for those that are
creating the print spaces (those that write QTR curves, IJC curves or RGB
curves such as Paul's).  If that mapping is quantified and then made
available with the curves then the vast majority of the monitor vs print
issue will likely disappear.  Any residual mismatch will in very large part
only be due to poor monitor profiling.

It's worth winding back a little to how QTR - Gray Lab and QTR - Gray Matte
Paper and QTR - Gray Photo Paper came about, and even before.  Quite some
time ago there was a discussion as to what the right "linearization" in RIP
printing was and it was generally agreed than a sensible practice in RIP
development was to linearize the printer such that Lab's L(uminance)
readings were linear, ie that in stepping from paper white to ink black the
progression in L would be uniform and linear.  There was then a lengthy
discussion about how we typically worked in Gray Gamma 2.2 but the print
space was linear L from paper white to ink black and, importantly we were
using a Same as Source workflow (meaning there was no translation mechanism
in going from the image workspace to the print space).  Given we are using
Same as Source, the closer the two are aligned the better and hence the
discussion of editing in Lab (rather than Gray Gamma 2.2) and Roy's
derivation of Lab without the a and b channels:  QTR - Gray Lab.

But is is easy to see that even with an image in Lab or QTR - Gray Lab there
is still a marked difference between the workspace and the print space for,
say, matte paper.  Take a piece of paper and draw a chart with L on the
vertical axis and normalised pixel value 0-100 on the x-axis. (By normalised
I mean that whether the image is recorded in 8 bit or 16 bit the scale has
been normalised to 0-100.)  If we were to plot L values for Lab or QTR -
Gray Lab the line would go from (0,0) to (100,100), ie from pure black/L=0
to pure white/L=100.  Now write "darker than Lab" in the area below the line
and "lighter than Lab" in the area above the line.  QTR or IJC have implicit
in their curve creation a linear progression of L from paper white to ink
black, as noted above. But if paper white is L=96 rather than 100 and ink
black is L=16 rather than zero we have a very different profile than the Lab
workspace.  Plot the line from (0,16) to (100,96).  From the chart it is
easy to see that the vast majority of images would, in these circumstances,
print lighter than displayed on screen. We would also note that they would
appear flat - the slope of the line is much flatter than the Lab line:
there was reduced gamma and reduced dynamic range.  Therefore we still faced
two issues.  Firstly, the images would still not print as they were
displayed.  Secondly, the linear mapping of images to the print space would
produce "flat" images.  Dealing with previewing the image as it would print
is actually the easy part.  A simple PS curve can depict the print space
quite easily (using the % scale shift the white point to (0%,4%) and the
black point down to (100%,84%) and leave the line straight in the middle).
Carl Schofield also developed a way to use an Eye One to generate an ICC
profile-based soft proof. The more difficult issue was to remap on a more
satisfactory basis (not one-to-one mapping) from the workspace to the
narrower print space and produce a more visually pleasing print.  This was
the big step forward that Roy took in providing us all with the Matte Paper
and Photo Paper ICC profiles.  Now we can use PS's colour engine with
Perceptual Intent to map from the workspace to the print space and produce a
more visually pleasing print in the narrower space.  In fact, it does away
with the need for working in Lab or Gray Lab, we can stay in Gray Gamma 2.2
if we so please because we have an engine for moving from the workspace to
the colour space - we are no longer using a Same as Source workflow.  The
second advantage this gave was that since the mapping uses an ICC profile we
can use PS's soft proofing features for an accurate preview of the printed
image.  In other words, we dealt with the second leg of issue I noted in my
first paragraph.  Any other residual mismatch between screen and print is a
technical problem associated with either a poor monitor profile or some
mismatch between the generic profile provided by Roy and any
printer/ink/paper specific issues.  The success of the generic profile is
indicative of the fact that my second issue leg is the critical one, much
less so the first.

Now there remains the issue of those workflows that remain Same as Source.
Quite understandably Paul's workflow and the BO workflow are still grappling
with the "matching monitor to the print issue".  Not only might they have to
deal with poor monitor profiles but they still haven't provided a solution
to the second larger issue of providing a mechanism for previewing the
mapping from workspace to print space.  I would suggest that this is
actually easy to do and can be readily provided to others using those
workflows who do not have access to the equipment necessary to do it.  I
would also suggest that focus be given just to the larger, second of the two
issues I noted.  How to do this?  There are two methods that come
immediately to mind.  One requires a densimeter only while the second
requires an Eye One Photo.  Remember I am not suggesting that everyone needs
access to one of these - just those developing the curves for that workflow.
Let's use Paul's workflow as an example. If he had access to an Eye One, for
example, for each of his developed curves (eg 2200-UT7-EEM-Neutral) he could
follow Carl Schofield's soft proofing technique and provided with each curve
an ICC soft proof profile which could be used while working up an image.
(Note, Paul doesn't face the issue faced by QTR and IJC on how to map from a
linear workspace to a narrower linear print space - he maps this by hand as
part of developing his curves.  He simply faces the issue of portraying this
on screen.) Someone with access to an Eye One could also provide a BO 1.8
and BO 2.2 ICC profile for a printer/paper/ink combination. Alternatively,
if, say, Paul does not have an Eye One and so can't take advantage of Carl's
soft proof technique or can't find a similar technique that works with his
existing spectrophotometer, then he can measure the L values of the steps in
a step wedge printed with each of his curves and translate those into a
"soft proof PS curve" (by comparing the output with the input) which could
be applied by people using his workflow when working up an image.  Once the
image was finished and ready to print the soft proof curve can be discarded
and replaced with his RGB print curve.  Then the image can be printed.  A
like procedure can be done for BO.

The big point here is that, I believe, the bulk of the issue that people
grapple with here is not actually monitor profiling/calibration but rather
the lack of an automated way of presenting the image in the print space.
QTR has overcome this hurdle (anyone using QTR with Same as Source really
needs to get themselves up to speed with the new developments) and, in fact,
has largely solved the issue for IJC/OPM users as well.  For the remaining
Same as Source workflows, trying to deal with the two aspects of the issue
at once mean that each person must deal with it - even though the first leg
of the issue is likely relatively minor compared with the second which, in
turn, is largely common to all.

If one comes to grip with the second leg of the issue - the mapping from
workspace to print space - there is little need to dumb down your display.
You can keep the dealing of the second leg dynamic - capable of responding
to new inks, papers, printers etc.  Furthermore, other aspects of using your
computer and its display are not affected, for example the ability to view
other people's images online in a sensible manner.  To make this point
again, imagine dialling down your display's black point so that it equalled
your dMax on matte paper - just so that you got a better match between your
matte prints and the display.  Now ANY image you look at on your display
takes on this dull black point.  Looking at someone else's portfolio on the
web would not do those photos justice. You can't even see how your own work
would look if it were printed on photo paper because your monitor would
understate the black.

This is why I react strongly against "tweaking the monitor" to match the
print.  You really are shooting yourself in the foot and starving your
equipment of the right to serve you well.  Not everyone can afford the
equipment to profile their monitors - even at today's price points.  But to
take a good piece of hard earned equipment and chop its functionality to
pieces really doesn't make sense.  An Apple computer has the ability to
profile a display and it is my understanding that the PC version of PS
retains the ability to profile a monitor using Adobe Gamma.  Even if these
are the only tools you have available for profiling your monitor, use them
and use the colour management tools inherent in PS (or your other image
editing tool).  And then understand the other aspects of your digital
photography which explain why there are any, if any, differences between
display and print.  Those that generate the curves used in the various
workflows out there are in a position to help with the differences. They
have been awfully generous with their time thus far - if we ask them nicely
perhaps they can help further.

Steve