Digital BW, The Print

What I'm trying to do is find a good way to see how smooth (or not) the
grayscale ramps are on the various inkjet workflows.  It is, perhaps, a way
to judge the extent to which the workflow can produce smooth, photographic
prints.

The procedure I tried here (and would like some feedback on) was to run a
Photoshop gradient at 50% opacity over and the opposite direction of the
21-step gray scale smooth ramp of the scanned test strips being compared.
The purpose of this procedure is to neutralize the ramp -- except for those
parts of the printed ramp that deviate from the Photoshop gradient ramp that
was used to make the test file in the fist place.  What should stand out, I
hypothesize, is the defects in the printing system/workflow.

To further accentuate the defects/deviations, I increased contrast 90% and
brightness 30%.

For comparison, I used one Piezo 1160 test strip (Piezo ink and driver ver.
5.1.3 on EAM with EAM profile) and one test strip printed with the 3000
using the VM-sepia ink with the neutral curve (a modified vm "warm" curve)
and, of course, the Epson driver.  This print was also on EAM.

Both test strips were then scanned at the same time.  (The scanner has a
defect that put 2 lines in the shadows of both test strips.  One is in the
100% patch and one in the 95% patch.  They are obvious in the image because
they are the same for each test strip.)

We are, of course, familiar with the dots that the 3000 has with the Epson
driver, and the dots do stand out.  So this comparison shouldn't even be
close. Right?

Take a look at the scanned image.  It is in the Files section, which is at:
http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/files/

Then go to > Inksets, reviews and techniques and see "Ramp-smoothness.jpg."

(The full URL is:
http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/files/Inksets%2C%
20reviews%20and%20techniques/Ramp-smoothness.jpg

But Yahoo mail wrecks the ability to click on wrapped URLs.)

Piezo wins the dot contest easily, but it has lots of vertical lines in it.
Overall, the contest is rather closer than one would expect.

The reason I originally started making Photoshop curves to print Piezo inks
with the Epson driver was to get smooth skies in some photos that Piezo was
putting lines in.  I suspect the vertical lines in this test are what was
causing the trouble with the Piezo outputs.  It would be interesting to see
how version 6 and the 7000 Piezo software does.

Of course, I don't expect to see perfection in any ramp, and I'm sure most
of the vm curves that I've done are even more defective than the one used
here (which is a new one just for the VM-sepia inkset to give a neutral
print).

I think this test is consistent with the comments we've heard lately
comparing digital and darkroom prints.  I think we still have a ways to go.

Paul
http://www.PaulRoark.com