Eugene,
I think I get what you are saying -- see if this is what you mean.
You have a printer/ink/paper combo that goes from L*16 to L*100.
For editing you are using GG2.2 so L*16 is about K=83.
So while editing you are using and seeing K=0 through K=83 thus
seeing specifically the L* range of the paper. Then when you print
you expect L=100 to map to white paper (no inks) and K=83 to
map to the L=16 dMax -- and probably all the L 's in the middle match.
Sounds kind of nice in general -- but I guess I've never heard anyone
doing it this way. I think people in general use generic workspaces
like GG2.2 -- edit as they like on the screen. Then that's a "master"
image file that you can print to matte paper, photo paper or web sites.
The mappings are always K=100 to K=100 even if K=100 on the
paper is L=16 or L=4. ICC CM is the tool that does this mapping in
a way that hopefully does a "best" job given that compression.
In your way you give up 17% of the range in GG2.2 -- 8-bit that would
be an issue but with 16-bit its probably not serious. (there still are 8-bit
places in workflow though). More of an issue though is that now you
have to have separate masters for different targets -- i.e. matte master
and photo master, and maybe for different individual papers.
Essentially you are editing in a "print" space rather that a generic
space that you can convert as needed for any print space. I see the
whole ICC profiling purpose is to get away from that.
This is my impression about how most people do things. I'm certainly
more in the B&W world than color, and I don't do ad's that have to
match specific colors, nor try to make exact L-value targets or something.
Of course, I don't profess any absolute of how you should do a workflow.
Roy
On Sun, Jul 31, 2016 at 7:58 AM, Le Mois de la Photo à Uqbar info@... [QuadtoneRIP] <QuadtoneRIP@yahoogroups.com> wrote:
-- Roy,
“You need to try it. I don';t know what you are really trying to accomplish”.
This surprises me , it makes me feel like I’m from another planet. But maybe I am in some respects I’m getting the feeling that my perception of the ICC workflow is actually a completely different school of thought to the QTR workflow .
In the ICC workflow that I am familiar with the media type settings ( ink level curves) do not remap file data to maximum black, colour management does.
So in that light this is what I mean to accomplish is
Obviously The L*0 to ( roughly L*3 -8 for glossy papers or L*17- L*22 for Matte papers) values of the image file have to be moved to the maximum ink level of the paper /printer combination. In the dark room we made test strips to determine precisely where Dmax yielded to the first visible tone. In the ICC work flow I only know of 3 ways to accomplish this, either; a conversion using perceptual rendering to the output profile, a conversion using relative rendering in conjunction with Adobe Black Point Compensation or a conversion using relative with no BPC where the black point has been manually targeted beforehand. Perceptual rendering and BPC are like automatic modes. I have never fully understood the behaviour of BPC especially where colour data is concerned, and since I’m a control freak, I prefer to do it myself.
When I print a chart of the 100 L* values in an ICC workflow with relative intent and no BPC I can verify ( under lighting conditions the final print will be displayed in) exactly where DMAX is lost and the length of the toe,( the distance between the first appearance of visible line and a usable threshold density). This allows me to see which paper/ printer combinations take as much as 5 L* to move from the first visible line to usable threshold density, and which paper/ printer combinations can make clean and clear tonal distinction rapidly. The elasticity of this dmax to usefull threshold zone allows me to place whatever deep shadow detail I do not want to be printed with anything less than useful threshold density, precisely there. Then once I’ve compressed the curve by targeting the black point and threshold I can use a target curve with soft proofing to realign the L* axis should I feel the uniform compression fused contours, or simply to readjust local contrast, especially if vital vibrations from tonal juxtapositions were diminished by the uniform compression.
As a said previously I have the feeling the QTR workflow attempts to do this with ink level curves.
I can’t believe that this approach is alien to you I have to believe I’m not expressing myself properly. I hope this detailed description helps.
Eugene