Digital BW, The Print

This new non-blended ink approach has sat in my 7500 for 2 weeks now.  So,
to see how stable the tones were, I printed a test strip, read the patches
with the PrintFixPro Spectro and graphed the Lab A and B values with Excel.
I've overlaid the graphs, matching the paper white and black points to
adjust for spectro reading errors to at least some extent.  The results are
posted at 

http://home1.gte.net/res09aij/7500_4K+_PA-N1_B_14_Days.jpg and

http://home1.gte.net/res09aij/7500_4K+_PA-N1_A_14_Days.jpg

I'm very pleased with the results.  The deviations shown on the graphs are
close to the expected random errors from different dry times, the spectro
and other factors.

So, this is the inkset I'll be using in the 7500 for a while.  It gives me
full Lab A and B controls, and appears to be very stable.

The old 7500, with its relatively large and non-variable dots, does show a
very fine grained dot structure on test strips when viewed with the
strongest reading glasses.  However, for display prints, I think the
smoothness is fine.  Compared to the blended inkset I was using previously,
the current one is about 15% less smooth according to the average Standard
Deviation measures of 1600 dpi scans.  Again, the fine grained structure of
the image is essentially irrelevant to me for display prints.  The stability
of the tones and full Lab A and B controls are far more important.

So, I'm very happy with this combination at this point.

For the details of the inkset, see below.

Paul
www.PaulRoark.com 



On October 01, 2006 I wrote: 

>I'm trying a new inkset in my 7500 as a way to simplify my 
>life and, hopefully, cure the tone shift problem I've 
>experienced in large format printers running dedicated 
>"blended" B&W inksets. 

...

>This approach will only work with a rip, with QTR and IJC being 
>the logical ones for most B&W printers.

>Currently, this is what I have loaded in the 7500 (source 
>of ink in parentheses), and I think it will for fine for 
>all 7000 and 7600 generation printers:

> 4 k's: 

> - MK (MIS - Eboni), 

> - PK (now MIS, may be Epson later), 

> - LK (MIS), 

> - LLK (MIS);

Plus colors:

> - Light Cyan -- 50% MIS Light Cyan, 50% clear base for 7500;

> - LM (Epson UC, may be Epson Archival later).

> There are no blends of more than one type of pigment in any ink. 
> As such, the inkset should be relatively easy to profile and 
> should have the least amount of color drift between printing sessions.

> All inks can be off-the-shelf and from multiple sources. For 
> the 7500, however, I do think the lighter 50% LC ("LLC"?) 
> is worth the effort for smoother highlights. It's an easy 
> 1:1 mix of readily available and compatible cyan pigment and 
> clear base [or Glop]. MIS's cyan pigment appears to be very good.

> With both MK and PK loaded, I can print on either matte or glossy paper.

...