Digital BW, The Print

I just wanted to get back with an update here- I spoke with Walker this
afternoon (thanks for taking the time to chat with me by the way!), and
though I'll be the first to admit that I'm still out of my depth with some
of this, I do feel like I'm getting somewhere.  I'll relay what I've done so
far, for the benefit of anyone who may be wanting to try this, and by
talking it out, hopefully it will become apparent where/why I hit a wall
this afternoon-

 

Ok, so after building and profiling my print environment, I converted an
untagged RBG gray patch file to the new CMYK profile in PS, using relative
with BPC.  I then printed it through my new environment set to Rel+BPC.
After reading the patches I inverted the A&B values of my LAB measurements,
so that a "0.51" became "-0.51" and so on.  I then saved this file as a .txt
and applied it to the QTR createICC RGB program.  I dropped the created
profile into the input profile folder for Studioprint, and as long as I went
back to my original untagged RBG gray patch file (or any RBG file), the new
QTR profile was listed as an input profile option (if I tried to use the
CMYK converted gray patches I originally printed, it was not an option since
the QTR profile is RGB).  Then I printed the untagged RBG patches, using my
new input profile, and rendering set to Rel+BPC (since that's what I used
for the chart, I will need to use that all the way through, right?)

 

This is where things get hazy.  After the next reading, some of my AB values
are indeed closer to the line (0), but some remain the same, and if I
remember correctly, some have gotten further from it.  If I repeat the
inverting step again, my next readings are much the same, though this time
some definitely have gone the wrong way.  In addition to that, my luminance
values begin to get a little hinky, and linearization seems to go.  Now the
question is what went wrong. if anything?  Did I maybe just take it too far?
Should I have left it alone after the first input profile was created, and
considered that close enough to neutral to begin tuning?  Is this evidence
of SP misbehaving with input profiles, or as Walker mentioned, perhaps
double profiling is causing a problem with that first set of patches, and
the problem is just carrying down the line.

 

So many steps. so many places to go wrong. lol

 

Even with the maddening nature of this work, I'm still really excited about
the potential.  Being able to hang a matching 60" print from my 11880 next
to one from my K7 selenium would be a marvelous thing.  Or here's something
else Walker and I discussed today- take it one step further, and be able to
"capture" for lack of a better word, the hue of an existing print and be
able to reproduce it (I'm thinking something to do with a scan, maybe a
blur, and some way to automatically find the luminance values to correspond
to your gray patches).  That would seem a unique opportunity to preserve
some of the classic silver tones, but also bring back those that are already
gone.  Artistically and aesthetically it would be fantastic, plus from the
service bureau side of things it would be so nice to actually be able to
match the new with the old. 

 

Walker mentioned creating a website where people could share LAB values for
all manner of different prints, I think that would be a fine idea indeed!

 

 

 

 

  _____  

From: DigitalBlackandWhiteThePrint@yahoogroups.com
[mailto:DigitalBlackandWhiteThePrint@yahoogroups.com] On Behalf Of Ernst
Dinkla
Sent: Friday, April 23, 2010 4:20 PM
To: DigitalBlackandWhiteThePrint@yahoogroups.com
Subject: Re: [Digital BW] Re: B/W options for 11880?

 

  

It all recalls some memories of using my Epson 9000 with a custom quad 
set + the Wasatch SoftRip. That was before QTR existed. Converting a 
greyscale TIFF to a CMYK TIFF where each channel had the same content 
the greyscale TIFF had. Taking out one channel of CMY with a zero curve 
in the RIP so no black generation happened and applying 3 curves for the 
remaining 5 channels to fit the grey inks. Linearisation as available 
in the RIP per channel but not on the total partioned result. It worked 
but what a hassle. It was nice to be there when QTR was created.

BTW if that would be a route then you can download the odd greyscale to 
CMYK converter here:

http://www.pigment- <http://www.pigment-print.com/Quad%20QTR/Index.html>
print.com/Quad%20QTR/Index.html

-- 
Met vriendelijke groeten, Ernst

Try: http://tech. <http://tech.groups.yahoo.com/group/Wide_Inkjet_Printers/>
groups.yahoo.com/group/Wide_Inkjet_Printers/

| Dinkla Grafische Techniek |
| www.pigment-print.com |
| ( unvollendet ) |





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