QTR-Quadtone RIP

Hi

I think your problem might originate from your test file/methodology.  The
Northlight step wedge I found at their website was test-ramp.tif. If that's
the file you used, you will note that it is an RGB file. To my eye, the
shadows in that image look compressed to start with. That said, since test
file is (supposedly) ready for printing, you should not "Convert" it to
QTR-Gray- Photo Paper profile. You should either print it as is or "Assign"
the QTR-Gray Photo Paper. That will change its appearance on the monitor,
but not the data. Actually, you can't assign the QTR-Gray-Photo paper
because the file is RGB, but you can assign the QTR-RGB-Photo Paper profile
and convert to QTR-Gray Photo Paper.

You might want to read Roy's notes in gray-readme.doc in the QuadtoneRIP\ICC
folder.

In response to the remainder of your question, to adjust the appearance of
your prints you can:
1.	use the quick but ad-hoc approach of modifying the Shadow and Gamma
sliders in QTR before printing.
2. Since you can measure L*, you could modify the curves and re-linearize
using the Curve Creation tools.
3. Finally you can print a step wedge (I suggest Roy's 21step or 51step
files) and use the QTR-Create-ICC tool to create an ICC profile for your
curve/printer/ink/paper combination and use that to preview your image in
PS.

Tom Moore

> -----Original Message-----
> From: QuadtoneRIP@yahoogroups.com [mailto:QuadtoneRIP@yahoogroups.com] On
> Behalf Of prof_mgt551
> Sent: Thursday, May 25, 2006 10:32 PM
> To: QuadtoneRIP@yahoogroups.com
> Subject: [QuadtoneRIP] How to adjust Ilford Pearl Curve?
> 
> I just started using QTR with an Epson 2200. I downloaded and
> installed the UCpk-IlfordSmoothPearl curves that Tom has so generously
> provided. I made a test print using the Northlight Images standard
> test file that I first converted in Photoshop to the QTR-Gray Photo
> Paper space (using the icc file located in the QuadToneRip ICC
> folder). I am  using the Photo black ink and a Windows XP machine.
> 
> QTR Settings: 80 cool 20 warm, ink adj 0, gamma adj 0
> The print overall looks good except the deep shadows start losing
> detail. Step 100 measures L 5.40, step 95 measures only L 6.34. From
> step 90 and on, the L value measures much more separation between each
> step and you can clearly see the steps.
> 
> What options are there for opening up the deep shadow between step 100
> and step 95. The rest of the gray scale looks pretty good and the
> tonality is close to what I see when viewing in Photoshop. I don't
> want to adjust the ink level since solid black is nice and deep. I
> don't want to use the gamma slider and open up the shadow at the
> expense of the mid-tone.
> 
> Are there any other tools in QTR that could be used to make this
> adjustment or modify the curve?
> 
> Thanks for your help.
> 
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