Digital BW, The Print

Actually, Lou, I also got higher Dmax, in the range you speak of, when I tested for the max point on the curve vs % K. Forget the whole thing!

Ian




Message: 13        
   Date: Thu, 24 Mar 2005 01:57:23 -0000
   From: "Louis Dina" <lbdina@...>
Subject: Re: A Definitive B&W Pring; Dmax


Ian,

If I understand you correctly, you asked the Epson driver (using the 
full color inkset) to print a Photoshop grayscale image with K values 
in increments of 1, from 1 to 100.  

In full color mode, the Epson driver is not using JUST the MK or PK 
ink, otherwise you would get a very warm brown/black.  Within its 
driver, Epson has it's own proprietary formulas to blend various inks 
to get the most neutral black and the best Dmax.  Depending on the 
paper, that formula differs, just as it would if you created your own 
profiles using QTR or IJC/OPM.  You may or may not need more than 
just the MK or PK ink to reach Dmax, and you definitely would to get 
a neutral black.  I typically add some Cyan and Magenta to either MK 
or PK in the shadows, both for neutrality and to shoot for the best 
Dmax.  It's a trial and error process to get the best combination and 
compromise.

Actually, I have been able to easily exceed a Dmax of 1.96 on 
Kirkland Glossy with IJC/OPM using the Epson UC inkset with the PK 
ink.  I forget the precise number, but it was between 2.2 and 2.4.  
This was measured with my Eye One spectrophotometer.

So, if my understanding is correct, your test really isn't apples vs. 
apples.  If the Epson driver were really good at getting the best 
Dmax and metameric free monochrome and B&W prints without color 
crossovers using the OEM inks, it is unlikely most of us would be 
using 3rd party software or inks.  

Regards,

Lou