Digital BW, The Print

Roy,

Thanks for your help about a month ago
<http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/message/43660>.
 I've resolved the initial problem, which I misunderstood how to set
the profile.txt for the ink limit test.  I'll follow-up privately so
as not to confuse anyone else in the group.

I'm curious if you or anyone else has first hand knowledge of getting
a 1280 w/Cone inks profiled.  My current setup, compatible w/the Cone
plug-in (& not the new ICC profiles) is:

Black = Museum Black
Cyan = PiezoTone Selemium, cyan/light cyan postion
Magenta = PiezoTone Selemium, magenta/light magenta postion
Yellow = PiezoTone Selemium, yellow postion
Light Cyan = PiezoTone Selemium, cyan/light cyan postion
Light Magenta = PiezoTone Selemium, magenta/light magenta postion

After I established the ink limit for each channel, I created &
installed a new profile.  The ink pattern page printed in calibration
mode has a couple of interesting characteristics.

The first is that the 100% black patch density is 1.52.  This seems a
bit low compared to the final target density of 1.6 to 1.7.  May be
I've jumped the gun & should wait for the complete profile.

The 100% cyan patch density is 1.19 and the light cyan patch is 1.12.
 This is not a measuring difference.  This is a printer difference.  I
don't know if there is a variation in the ink bottles or if the heads
are slightly different.  The difference is very consistent, however.

The same holds for magenta - 0.62 and light magenta - 0.66.  As long
as I compute the relative darkness to black seperately, my assumption
is QTR will handle the rest.  Other alternatives include using only 4
out of the 6 heads. 

Thanks for any insights,
Dave G.

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Roy Harrington"
<roy@h...> wrote:
> 
> Hi Dave,
> 
> I think the first problem is that you are getting too much ink on the
> paper.  I don't use HWM in general but the ink limit of 80 seems
> too high.  When you get too much ink very often you get a reversal in
> the densities such as you 100% being less dense than the 90%. 
> I would try a default ink limit of 70 or maybe even slightly less
like 65 to 69.
> Also the BOOST_K value should come down to about 80 or so.
> With so many grays you probably don't need the GRAY_OVERLAP,
> i.e. make it 0 (this is extra overlap the basic curves do overlap
already).
> This would reduce the total quantity of ink in the paper as well.
> 
> Its strange that your LC and LM inks don't match the C and M inks
> -- they are supposed to be the same ink.  But its not really a problem.
> Once you reduce the ink limits, print another inkseparation page.
> (the CMYK file was the older version but it only worked on jaguar,
> the newer RGB file now works on both jaguar and panther).
> 
> From the inkseparation page you should first order the inks by
> density -- it looks like the LM should come before M -- and 
> calculate values for GRAY_VAL's.  The 40,11,6 are probably close
> but if you do it more accurately the ramps will be smoother.
> 
> Finally when you do the linearization all the density values should
> be increasing -- if it levels off or decreases you still have too much
> ink.
> 
> Try this all out and if there's still problems let me know.
> Once you get a good profile if you'd like to share it with others
> I'd be glad to include it on the download page.
> 
> Roy
> 
> 
> --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "dgabbe2001" 
> <dgabbe@a...> wrote:
> > I'm having a bit of trouble getting QTR Beta 9 working on my OS
> > X10.2.8 system and Epson 1280 w/Piezo Selenium inks on Epson Heavy
> > Weight Matte.  All my problems are around partitioning &
> > linearization.  I'm hoping these problems have been seen before....
> > 
> > I started w/the 1280-piezo.txt, added my curve name, printer name, &
> > set calibration to 'yes'.  The magenta & light magenta positions have
> > the same inks as do the cyan & light cyan positions.  I printed the
> > inkpattern.psd (cmyk).  I also have inkseparation.psd (rgb).  The
> > instructions for calibration referenced the cmyk file.  I don't know
> > which file is the current one.
> > 
> > I printed out the file following the calibration instructions - output
> > mode was QuadtoneRip calibration.  The spectrocam device measured 100%
> > cyan to be 1.22 and the 100% light cyan to be 1.09.  100% magenta is
> > 0.58 and 100% light magenta is 0.67.  I waited about 5min for the
> > paper to dry a bit before measuring.  The patches look different just
> > by eye.  I was not expecting such a large difference.  How have other
> > people handled this situation?
> > 
> > I turned off calibration mode & created a new profile.  At this point
> > I should have a set of curves for just the basic partitioning.  Next I
> > printed 21step.psd & measured the density of the patches.   My 100%
> > black measured 1.45 and the 95% patch measured 1.56.  Seems like the
> > 100% patch is not overprinted w/the dark gray. My linearization entry
> > is below in my curve file.  Then I generated a new set of curves. 
> > Note I didn't have calibration turned on.  Any suggestions?  Having
> > 100% black less dense than 95% black makes for interesting output. 
> > What is the correction for this issue?
> > 
> > Thanks,
> > Dave G.
> > 
> > My curve file below:
> > 
> > #
> > #  quadtone curve descriptor file
> > #
> > #
> > # the printer name
> > # the curve name
> > #   no spaces or special characters, except - or _  (dash or
underscore)
> > #
> > PRINTER=Quad_1280
> > CURVE_NAME=PiezoSel-Mb-EHM03bb6102
> > CALIBRATION=NO
> > GRAPH_CURVE=YES
> > 
> > #
> > # number of inks must be 4, 6, or 7
> > # the ink limits are percentages
> > #   usually they are all the same but they can be individually set
> > #
> > N_OF_INKS=6
> > DEFAULT_INK_LIMIT=80
> > 
> > LIMIT_K=
> > BOOST_K=100
> > LIMIT_C=
> > LIMIT_M=
> > LIMIT_Y=
> > LIMIT_LC=
> > LIMIT_LM=
> > LIMIT_LK=
> > 
> > #
> > #  Describe Usage of each Ink: K,C,M,Y,LC,LM,LK
> > #    All Inks of Printer must be listed
> > #
> > 
> > #
> > # Gray Partition Information
> > #  use ink names: K,C,M,Y,LC,LM,LK
> > #
> > N_OF_GRAY_PARTS=6
> > GRAY_INK_1=K
> > GRAY_VAL_1=100
> > 
> > GRAY_INK_2=C
> > GRAY_VAL_2=40
> > 
> > GRAY_INK_3=LC
> > GRAY_VAL_3=40
> > 
> > GRAY_INK_4=M
> > GRAY_VAL_4=11
> > 
> > GRAY_INK_5=LM
> > GRAY_VAL_5=11
> > 
> > GRAY_INK_6=Y
> > GRAY_VAL_6=6
> > 
> > GRAY_INK_7=
> > GRAY_VAL_7=
> > 
> > GRAY_HIGHLIGHT=4
> > GRAY_SHADOW=8
> > 
> > GRAY_OVERLAP=10
> > GRAY_GAMMA=1
> > GRAY_CURVE=
> > 
> > LINEARIZE="0.0 0.09 0.18 0.29 0.40 0.51 0.62 0.67 0.75 0.81 0.89 0.94
> > 1.01 1.06 1.14 1.33 1.37 1.44 1.46 1.56 1.45"
> > 
> > #
> > # Toner Partition Information
> > #
> > N_OF_TONER_PARTS=0
> > TONER_INK_1=
> > TONER_VAL_1=
> > TONER_INK_2=
> > TONER_VAL_2=
> > 
> > TONER_HIGHLIGHT=0
> > TONER_SHADOW=0
> > 
> > TONER_GAMMA=1
> > TONER_CURVE=
> > 
> > #
> > # Unused Inks
> > #
> > N_OF_UNUSED=0
> > UNUSED_INK_1=
> > UNUSED_INK_2=
> > UNUSED_INK_3=
> > UNUSED_INK_4=
> > 
> > #
> > # the following is a special UltraChrome ink flag
> > # it copies the light-black curves to the light-cyan and light-magenta
> > inks.
> > # this insures that the LC and LM inks are used to directly neutralize
> > # the color of the light-black.
> > # the color balance of inks is controlled by the LIMIT_... values
above.
> > #
> > UC_NEUTRALIZER=NO