Digital BW, The Print

Hi Peter.

I see that Paul has already given you some feedback. Perhaps I can add a bit
flavour based on my own experiments.

I've experimented with an HP PK based inkset, a Canon 8300 "PK" based
inkset, a combination of the two, and finally the MIS PK based 6KPlus inkset
Paul describes on his website.

The HP PK set consisted of five HP PK dilutions made with MIS GLOP. On
Canson Platine, which is essentially a neutral (a* = 0.1, b* = 0.7) cotton
rag, fiber based gloss paper, I ended up with a warm-toned image with a* and
b* values in the 1.0 to 2.5 range for most of the tonal range. It was a very
pleasant "brown" look given the relatively even mix a* and b* values,
instead of the more yellow look we generally see when b* far exceeds a*.
Dmax on Platine was 5.26 / 2.23 (Lab / Density). Harman Gloss proved even
warmer with the dilute HP PK inkset, having a strong yellow component (b*)
between 35% and 85% with a peak of 6.0. Harman Gloss Dmax was 4.74 / 2.28.

I was going for a more neutral look on Platine, my target media, so I
decided to experiment with Canon's 8300 "PK" ink (they call it BK). Canon's
inkset is quite neutral and the Dmax on gloss media is very high.
Unfortunately, Canon's PK is very warm (typical carbon) and they use their
LK and LLK equivalents (which are indeed neutral to slightly cool) to
deliver neutral blacks on the 8300. I picked up a Canon GY cartridge
(somewhat denser than Canon LK) and made three more dilutions from it for a
five dilution Canon inkset. I ended up with fairly neutral highlights to
mid-tones, but I had a large b* value peaking around 85% due to the very
warm Canon PK. Through some very clever curve building tricks Paul suggested
I was able to develop a near-neutral curve with values largely <1 for a* and
b*. However, bronzing and gloss differential were issues that I could not
offset, even with a spray. Adding some HP dilutions into this made with
Pauls C6 base did not alleviate the bronzing problem, which was at an
unacceptable level.

So, I more recently moved on to Paul's 6KPlus inkset. At first I tried
Canon's PK as the "K", along with the MIS PK dilutions, since I liked
Canon's PK Dmax. I had been able to achieve a Dmax of 3.40 / 2.42 on Platine
and 2.52 / 2.55 on Harman Gloss using the Canon PK, which was very
attractive. However, I was unable to address a non-linearity in the shadows
so I moved to the full MIS 6KPlus inkset as Paul defines it.

The good news is that 6KPlus is working very well for me on Platine. I have
a Dmax of 3.10 / 2.46 using MIS's PK which is excellent, and I have neutral
prints for all intents and purposes (a* and b* values < 1.0 for essentially
the entire tonal range and less than 0.50 for most of that range). There is
a bit of gloss differential in the specular highlights but no bronzing. The
image looks very cohesive, if that makes any sense, since I'm using
dilutions of one ink through the entire tonal range.

I am getting very straight, "bump-free" linearization's from my neutral
curve, which I was unable to get with the other inksets. I think the
overlapping LM and LC curves (required to neutralize the warm MIS PK
dilutions) address the artifacts and smoothes the curve.

I recently made a 16x24 fine art print on Platine using 6KPlus, sprayed it
with ClearJet A2000 gloss and mounted it glassless in an elegant black,
wooden frame. It looks great! I finally have an inkset I'm happy with, and
I'm looking forward to developing some warmer tones, and experimenting with
matte media using 6KPlus and Eboni.

There is one curiosity I've noticed. I get excellent Dmax with MIS PK on
Canson fiber based gloss papers, but the Dmax on other fiber based gloss
papers is not as strong. Here are the ones I've tested.

Canson Platine 2.52 / 2.55  (Lab / Density)
Canson Baryta Photographique 3.92 / 2.36
Harman Gloss Baryta 7.42 / 2.09
Museo Silver Rag (sample roll of latest product) 6.37 / 2.15

There must be something in Canson's coating that meshes well with the MIS
PK.

All of my testing was done on an Epson 2200, although the latest 6KPlus
results noted above (full MIS inkset) were from my Epson 3800. I should
mention that all of the inksets were reasonably clog free, although I had
some problems with the HP GLOP based dilutions (nothing I couldn't live with
however). 6KPlus has been very good in my 3800.

Peter, if you would like more information on any of the above, including
graphs of a* and b* values, just let me know.

Paul, thank you for the help, expertise and encouragement as I went on this
journey. In answering Peter's post I'm also trying to catch you up on how
things have turned out. Don't hesitate to drop me a note if you'd like more
details.

Terry.

On 12-09-04 2:00 PM, "Peter" <pdesmidt@...> wrote:

> I'm considering setting up a gloss printer, and I'd prefer neutral to mildly
> warmish tones.  In looking at Aardenburg tests, the piezography MPS don't seem
> to be doing all that well. As a result, I'm thinking about using HP PK as the
> basis of the inkset, as it's done very well in Aardenburg's tests.
> 
> As Paul's tests awhile show, the HP PK inks bronze quite a bit without special
> treatment.  The main options seem to be:
> 
> A.  Use MIS PK, which has less of a bronzing problem than the HP PK, and use
> glop to dilute the HP PK.  This would give warmish blacks with the rest of the
> tonal range being pretty neutral.
> 
> B.  Use all HP PK, and dilutions thereof, and use a second run through the
> printer to apply glop.
> 
> (Another option would be to use a spray sealer on the prints, but I don't have
> the space to make a spray booth.)
> 
> The HP PK is available in the HP 771 cartridge, product # CE043A.  It's a
> 775ml cartridge that sells for around $263.
> 
> A. would be the less expensive option, as the HP PK would only be used
> diluted.
> 
> Any thoughts or suggestions?