Digital BW, The Print

Hi Dave,

I haven't personally worked with the piezotone inks, but it all looks
like you are doing the right thing.   I'm not sure why you are getting
some variation in ink density -- are these numbers with all the same
ink limits?  I haven't any idea what consistency tolerance the heads
are made to.  The curves all blend one ink into the next very gradually
so it shouldn't present any problem.

Your dmax of 1.52 seems a little low but what paper are you using and
where did you get the target value of 1.6 to 1.7?

Roy


--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "dgabbe2001" 
<dgabbe@a...> wrote:
> 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