Digital BW, The Print

I also posted this exact same post at the QTR yahoo forum!

I have been very busy the last couple of weeks learning some of the idiosyncracies of QTR 
that I think could possibly be of interest to many, because some of the things I learned 
were surprises to me.

I was attempting to get a maximum dmax using the UT14 inkset, but this may apply to 
other inksets as well. The inkset I was using had a layout as follows:
ink 1 K = Eboni Black
ink 2 C = Cool PK
ink 3 M = Warm PK
ink 4 Y = GLOP
ink 5 LC = Dilute Cool PK
ink 6 LM = Dilute Warm PK

I was attempting to get the maximum black possible on a semi-glossy paper (ILFORD 
Galerie Gold Fibre Silk) using the PK inks, without using the Eboni Black which would 
require the use of GLOP, since Eboni doesn't adhere well to glossy type papers.

What surprised me after printing the inkseparation wedge at 100% was and taking many 
density readings was that I was getting a higher dmax readings with the DILUTE Cool and 
Warm PK inks rather that the expected UN-diluted Cool and Warm PK inks. I took many 
readings and double checked and noticed that even though the dmax decreased after a 
certain point with higher ink loads, as they do with some papers, that the highest dmax 
readinsg was with the two diluted PK inks; the Diluted Warm PK was actually higher (a 
little over 2.33 at 95% inkload) than the Diluted Cool PK (at about 2.15 at 100% inkload). 
The Cool PK in the C position was actually a little higher than the diluted Cook PK in the 
LC position (at 2.19), but not enough to mess with as you will see with my final result.

So what I ended up doing was creating a Warm curve using only the Diluted Warm PK ink, 
in the LM slot at 95 % inkload. With my "Cool" curve I ended up using the Diluted Warm PK 
ink in the LM position at 95% inkload for the darker blacks, and the Diluted Cool PK in the 
LC position at 100%, and at 76% of the Diluted Warm PK. You don't even noticed the 
diluted warm PK at this dark a black, but you do notice them being blacker, which 
accomplishes our goal of a maximum dmax.

After Linearization my final result was textbook ideal linear densities with a dmax of 2.27 
on both my Cool and Warm Curves.

Some other things I discovered for myself was that I achieved a much better linearization 
by adjusting the HIGHLIGHT, SHADOW, AND GAMMA settings to get as close to linear as 
possible before linearization; using these settings with it's resultant print of the 21-step 
wedge for the linearization readings.

I hope my comments may help some of you get the best profiles possible with maximum 
dmax,

Randy

"Randy Rancier" <randy_rancier2004@...> wrote:

> ... using the UT14 inkset, ...
> I was attempting to get the maximum black possible on a 
> semi-glossy paper (ILFORD Galerie Gold Fibre Silk) using 
> the PK inks, ...
> 
> What surprised me ... was that I was getting a higher dmax 
> ... with the DILUTE Cool and Warm PK inks ...
> ... the Diluted Warm PK was actually higher (a 
> little over 2.33 at 95% inkload) ...

That's an interesting result.  

With my dilute HP PK experiments I found I was able to hit a dmax of 
2.4 on Crane Silver Rag at a 100% QTR ink limit with a 50% dilution 
of the HP PK.  (I did not have a 100% HP PK test strip to see what it 
would do full strength.)  I attributed the result to the huge load 
the Crane paper could hold.  On most glossy papers the dilute ink did 
not do as well, coming in closer to 1.9.  I did not test the Ilford 
paper.

The MIS K4 PK is a lighter load (more dilute) than the older 7600 PK, 
I'm told, and it does work better on the newer printers, but on the 
older ones I think the more concentrated 7600 PK gives a better 
dmax.  So, it may be that, in general, a characteristic of the latest 
printers favors lighter load inks.

It would be interesting to see scans of the ink separation pages of a 
couple glossy papers if it's easy for you to post them somewhere.

Thanks for letting us know of your findings.

Paul
www.PaulRoark.com

Paul:
I'm getting a d-max of about 2.4 on the Ilford Gold Sylk, with my
Z3100. I'll check that again tomorrow when back in the studio.

Sounds like your HP ink dilutions are working well! Have you done any
research on exactly how HP is treating their ink to get the neutral tone? 

John Nollendorfs
--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "pr_roark"
<pr_roark@...> wrote:

>
> "Randy Rancier" <randy_rancier2004@> wrote:
> 
> > ... using the UT14 inkset, ...
> > I was attempting to get the maximum black possible on a 
> > semi-glossy paper (ILFORD Galerie Gold Fibre Silk) using 
> > the PK inks, ...
> > 
> > What surprised me ... was that I was getting a higher dmax 
> > ... with the DILUTE Cool and Warm PK inks ...
> > ... the Diluted Warm PK was actually higher (a 
> > little over 2.33 at 95% inkload) ...
> 
> That's an interesting result.  
> 
> With my dilute HP PK experiments I found I was able to hit a dmax of 
> 2.4 on Crane Silver Rag at a 100% QTR ink limit with a 50% dilution 
> of the HP PK.  (I did not have a 100% HP PK test strip to see what it 
> would do full strength.)  I attributed the result to the huge load 
> the Crane paper could hold.  On most glossy papers the dilute ink did 
> not do as well, coming in closer to 1.9.  I did not test the Ilford 
> paper.
> 
> The MIS K4 PK is a lighter load (more dilute) than the older 7600 PK, 
> I'm told, and it does work better on the newer printers, but on the 
> older ones I think the more concentrated 7600 PK gives a better 
> dmax.  So, it may be that, in general, a characteristic of the latest 
> printers favors lighter load inks.
> 
> It would be interesting to see scans of the ink separation pages of a 
> couple glossy papers if it's easy for you to post them somewhere.
> 
> Thanks for letting us know of your findings.
> 
> Paul
> www.PaulRoark.com
>

"sinar001" <jnolly@...> wrote:

> I'm getting a d-max of about 2.4 on the Ilford Gold Silk, with my
> Z3100. I'll check that again tomorrow when back in the studio.
> 
> Sounds like your HP ink dilutions are working well! 

So far so good.

> Have you done any research on exactly how HP is treating 
> their ink to get the neutral tone? 

One of the list members recently sent me and HP patent that appears 
to be on point.  I've posted it at 
http://www.paulroark.com/BW-Info/HPpat7452415.pdf

Assuming this is the one that relates to the HP neutral gray and PK 
inks, it looks like a neutralized carbon using the same general 
approaches we've used for some time.  The difference, of course, is 
that HP has access to virtually unlimited materials and resources.  
They appear to have put a lot of effort into matching the pigment 
characteristics such that the fade path will not go to green or the 
like on its way to carbon warm.  They may also be using a counter 
fade strategy like I used with the first FSN. 

Paul
www.PaulRoark.com