Digital BW, The Print

Many on this forum use QTR on Epson UC printers (2200, 400, 7600,
9600) 
using OEM inks.  We know that the "warm" profiles use only the black 
and light black inks, while the toned prints additionally use various 
mixtures of light cyan, light magenta, and yellow.  Because density 
across the 0-100% ramp is built up primarily from two desnity inks,
QTR 
OEM ink prints in general will be less smooth and more dotty in 
highlights.  This is only true at VERY close viewing distances and of 
no consequence for a print hanging on the wall or even prints viewed
on 
had at half arm's length.  Sadly I am one of those "print to the
nose" 
guys (perhaps I need to get a life!).

So what does it take to get better prints?  The original Piezpgraphy 
(and now PiezoTone) and MIS FS inks use 4 shades of gray (black, dark 
gray, medium gray, and light gray) to produce the absolute in ramp 
smoothness and dotless in highlights.  I asked myself is this
necessary?

The approximate ink density relative to black for Piezotone and MIS
FS 
inks are:

Black = 100%
Dark Gray = 55%
Medium Gray = 10%
Light Gray = 5%

In contrast for Epson OEM Matte inks

Black = 100%
Light Black = 35%

I have MIS FS inks loaded on a 1280, and went about creating QTR 
profiles using the following inks:

(1) Full spectrum (quad tone):  Black, Dark Gray, Medium Gray, and 
Light Gray.

(2) Partial spectrum (tritone):  Black, Dark Gray, and Medium Gray

On the 1280 (and presumably other newer printers that are smaller
than 
or equal to 4 pL droplet size):  The tritone prints are just as
smooth 
and dotless as the quad tone prints.  Both are better (very, very 
slightly)
than QTR prints uisng OEM inks.  My guess is that the Light Gray (5%) 
ink was essential in the older Epson 3000 printer which has a much 
larger dot size.

This has an important upshot, but only for advanced users who know
how 
to write profiles with QTR (or other RIPs which allow individual ink 
control).

The Piezotone inks are available in a number of hues (warm-neutral, 
cool-nuetral, cool-selenium, and sepia).  The ability to make decent 
prints using only 3 inks allows users to combine the hues in a single 
printer.  In contrast, on a 1280 using InkjetMall's Piezography ICC 
approach, one is stuck with a single hue.  

The 1280 is a 6 color printer and so it is possible to load black + 2 
hues (say cool-seleniun AND warm-nuetral) of Dark Gray and Medium 
Gray.  With this approach you have a 
redundant ink position which can be some sort of a toner, or used for 
full spectrum quadtone.  For this option you would need to fill your 
own cartridges or create a custom loaded CIS unit.

On the 2200, 4000, 7600, etc which are 7 color (neglecting the glossy 
Photo Black of the 4000), the upshot actually is very promising.  You 
can load THREE hues of PiezoTone inks.  InkjetMall offers 2 hues for 
these printers.  But because the light density ink appears to be 
superfluous, a custom approach will allow 3 hues and countless mixing 
between the hues.

Regards.

Shilesh