Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, Steve Kale
<stevekale@b...> wrote:
> I don't want to get caught up in semantics but really when we profile a
> printer with say an Eye-One we aren't calibrating. We don't change
anything
> the printer does, we don't tweak the printer control.  Rather we
_measure_
> how the printer renders pixel values and hence simply profile it. 
Colorsync
> takes this profile and does all the mapping from one profile to the
next -
> altering pixel values as necessary.  When we do change how the
printer acts
> for a given pixel value, telling it to put down x ink, I would say
we _are_
> calibrating it (rather than profiling it).  That is why I used the term
> calibration.

Of course, agreed to all.

> With regard to linearity, I clearly misunderstood you when you said:
> 
> "I need all those relationships to be proportionally maintained,
> absolutely, and that is what I think is generally accepted as
> linearization, even though that moniker may be incorrect by strict
> definition."
> 
> Apologies.
> 
> Call it output density adjustment or anything else, you are defining
what
> density the printer will print for a given pixel value.  Typically
> "linearization" refers to the last step in the process whereby the raw
> instruction set developed from partitioning is refined to meet a
particular
> curvature in the pixel value vs density graph.  Do we agree on this?  I
> think we do and this is good.

Yes, but "linearized", or "calibrated" to a selected standard, like
LAB, a dot gain, a gamma. I believe that was where the thread started,
which one, why, and whether the final output is in fact progressing by
that standard.

...
> Now we come to the question of whether or not we achieve the results we
> intend....
snip
> I would suggest that when someone says I want to linearize to LAB, for
> example, what they intend to achieve is a curvature of the pixel vs
density
> plot that matches the curvature of LAB.

...
and I thought we had concluded that that is indeed not what is
happening by the conventional use of the term.

> ...  What this would mean is that the
> printer would reflect a change in density for a change in pixel
value that
> matches LAB, how the eye sees and all that good stuff.  If it
doesn't then
> we have failed to meet our goal.  If you say "well who cares if it
doesn't"
> then I would say "why reference your target to anything then, let alone
> something which denotes a sense of rigour.  Pick any old number or
target -
> what the hell you can always soft proof the file and fix it with an
edit."

I don't think that is the case at all, there is clearly a usefulness
to selecting a target that is also the working space, and
"linearizing" by conventional standards referencing that target.
Clearly the resulting print bears a strong resemblance to the monitor
image, even without softproof.
That the entire curve has been proportionally compressed to match end
points clearly breaks from your particular goal, and a strict
technical definition of linearization to the selected standard, I'm
not arguing that.
I'd just like to use "clearly" in a sentence one more time.

I understand what you are after. All I am saying is that, despite it's
semantic inaccuracy, the conventional process works extraordinarily
well, is miles ahead of where we were before these tools were
available, and allows myself and others to achieve goals previously
barely attainable.

You are defining a different workflow and different end result, the
conventional approach to linearization may not be suitable for that as
you have been saying.

I'm sure my inconsistent use of terminology and ADD when it comes to
math is part of the problem here, I may not be the right guy to see
this conversation through. I suspect, though, that we are more or less
done and the approach I use, and the one so far used by many in the
community, is of little use to you.
I hope I haven't sounded like I'm trying to talk you into it, not at all.
I'd also add, in it's conceptual defense, that the craft (not the art)
of photography has always involved dealing with and/or matching the
range of the real world, through many steps and materials, down to the
range of a print. Scene to film, film to print, and now the same
concept in the digital realm with it's different steps along the way.
Not sure what more I have to offer here Steve, but I'll be watching
your progress with interest.
Tyler