Digital BW, The Print

> From: Paul Roark <paul.roark@...>

> 
> I printed a 21-step test print on EEM using my standard 2200-UT7-Neutral
> curve.
> 
> I then compared the print to my standard monitor view.  They did not match.

Yep - they couldn't for no other reason than EEM's black point is way less
than your monitor (presumably!)
> 
> So, I made a simple Photoshop curve that adjusted my monitor so that it
> matched the print.

> 
> I then made a second curve that I will call a "negative" of the first curve.
> I noted the amount I had to move the Output of the individual points on the
> first curve to get the monitor match the print.  I then moved the output on
> the second curve points that amount in the opposite direction.  So, for
> example, at 50% (AdobeRGB curve input 127), I had to move the default (127,
> 127) point up to (127, 132), a change of 5, on the first curve to get the
> view on the monitor to match my print.  So, on the second, "negative" curve
> I moved the point down to (127, 122), 5 units down instead of 5 units up.
> (At the 95% point this didn't work because the change was too much, so I
> just set it at half way to the 90% point.)
> 
> This second, "negative" curve I saved as my "Monitor" curve.
> 
> A made a small, new RGB file as a holder for curves layers.  On this file I
> made a curves layer set that had, as the first, bottom layer, my Monitor
> curve.  The second, top layer was my standard 2200-UT7-EEM-Neutral curve. I
> called the layer set Neutral + Monitor.
> 
> Then to print a test strip, I converted the standard 21-step test to RGB as
> usual, then I simply dragged the "Neutral + Monitor" layer set to the file
> and printed. 
> 
> The resulting print matched my monitor almost perfectly -- as well as any
> other system I've tried.

If I understand what you did correctly there ought to be an easier way.  You
created a neg curve and when printing sent this negative curve to the
printer.  Perhaps an easier way is to simply print a step wedge of your
workspace (no it doesn't matter which one you use so long as you understand
why it looks the way it does) with your normal print curve (eg
2200-UT7-EEM-Neutral) and measure the densities.  If you create a curve of
this mapping (or, as you did, do it by eye) you have a "preview curve" which
when applied to an image will show on screen how it will print.  Edit the
image to satisfaction.  When it comes to printing delete the "preview
curve".

> 
> If the monitor and print match, is anything else really needed?  Do we
> really care if the ramp matches Lab or any other space?

Depends.  You effectively define how your image workspace maps to your print
space by hand when you create your print curves.  I assume you look at the
output progression and alter 2200-UT7-EEM-Neutral until the step wedge
prints to your satisfaction.  Much as though you were manually doing
perceptual rendering and defining the ramp of your print space.

With something like QTR, the ramp of the print space is a linear progression
of Lab's luminosity from paper white to ink black by design.  Left alone
this print space is "flat" because we kept linearity but lost a lot of dMax
at one end.  So we could remap it by hand with a curve to get a more
satisfactory gamma from dMin to dMax (the old QTR s curve). (I used an Excel
spreadsheet for a while - I knew my QTR print space would be linear L from
dMin to dMax but wanted to remap the mid back to match the display and alter
the curvature about the mid.)  This remapping can be likened to your curve
construction process.  But because we know it has certain properties we can
use those properties to characterize it with an ICC profile, which Roy
magically did, and then use the other tools that come to hand via colour
management - an ICC managed workflow and PS' soft proof function.

The question I have for Roy is in doing the matte and photo ICC profiles
were they completely generic (ie just used a general L figure for dMin and
dMax and assume linearity between) or were they constructed by measuring an
actual step wedge - in the latter instance any residual non linearity would
be taken into account.

Steve