Digital BW, The Print

This is an interesting question (to me at least), so I thought I'd 
"bump" this thread and see what people with far more knowledge about 
this sort of thing than I have to say...

To add to the discussion though, I found the following information 
regarding the optical density (O.D.) for the Piezotone and the MIS 
Ultra-Tone (UT) ink sets at:

http://www.inkjetmall.com/store/info/1000-hours.html
http://www.inksupply.com/index.cfm?source=html/utfadedata.html

Below, I show the data just for Hahnemuhle Photo Rag paper. For the 
purposes of this discussion, I have not looked at the fade data, but 
just the given measured starting O.D.'s

The O.D.'s for the Piezotone inks (Warm Neutral though the other ink 
sets are similar) are as follows:

Light gray: 0.138
Medium gray: 0.241
Dark gray: 0.711
Black: 1.720/1.780 (Museum/Portfolio)

The O.D.'s for the UT inks are as follows:

UT-Y (25% Black): 0.500
UT-M (cool toner): 0.600
UT-LM (light cool toner): 0.640
UT-LC (50% Black): 1.340
UT-C (75% Black): 1.330
UT-LK (Light Black): 1.270
UT-K (Eboni): 1.750

Based on this data, there are a few conclusions that I draw:

- the lightest UT ink (UT-Y, "25% Black") is far darker than the 
lightest two Piezotone inks and is just a little lighter than the 
darkest gray Piezotone ink.

- the UT-LC ("50% Black") and UT-C ("75% Black") inks have essentially 
the same density, which strangely enough, is lighter than the UT-LK 
("Light Black") ink.

- The Ultratones have essentially three densities: 1) around 0.5-0.6; 
2) around 1.3; and 3) black.

- The Piezotones have four densities 1) around 0.15; 2) around 0.24; 
3) around 0.7; and 4) black.

- The Ultratones' range implies that separation between dark inks is 
more important, while the Piezotones' range implies that separation 
between light inks is more important.

So the question is: for those who have used/seen both ink sets, what 
differences do you see in the final output based on these different 
philosophies? Do the Piezotones have better detail or fewer visible 
dots in the lighter tones? Do the Ultra-tones have better detail or 
fewer visible dots in the darker tones? Other differences? I am more 
interested in the differences between "real" images, as opposed to 21-
step wedges...

Rik

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, Steve Kale 
<stevekale@b...> wrote:
> I think the general view is that 3 greys are not needed with the 
more modern
> printers.  I would still like Mac QTR to be able to print at 2880 on 
the
> 21/2200 though...
> 
> 
> > From: David Wroblewski <dawroblewski@y...>
> > Reply-To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
> > Date: Wed, 23 Feb 2005 22:04:12 -0000
> > To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
> > Subject: [Digital BW] Re: Epson R1800 vs 2200..need opinion fast
> > 
> > 
> > 
> > Great, thanks for the clarification. Is there any visible
> > difference between using K plus 2 grays rather than 3 grays?
> > 
> > I assume not--just curious though. The story I'm making up
> > for myself here is that quads used to be necessary but the
> > smaller droplet size on current printers allows us to go
> > to two grays without a visible difference in the print. Or
> > maybe it's better software?
> > 
> > In any case, that's a big deal, in my opinion.
> > 
> > -David
> >