Digital BW, The Print

Antonis wrote:

> 2. A 1280 printer loaded with MIS Ebony is way outperformed by a 7500
> with the same ink. Which goes to show that little desktop printers
> made for dyes may not give pigment black inks their best shot.
> Not really a surprise, but now confirmed in real tests.
> 
> 3. The 2200 with the Matte Black (marked as MK in the pdf) matched
> or outperformed wide format printers loaded with either the same ink
> or Piezo Museum Black. Often it was outperformed by Ebony in a
> 7500, however.
> 
> 4. UC Photo Black (in the 2200) outperformed the MIS UT Photo Black
> (in the 1160). The 1160 produced its darkest at step 23, well before
> the end of the 26-step scale. I am inclined to think that it wouldn't get
> any better with this ink on a big printer.
> 
> 5. In the large format category, Ebony in a 7500 often beats Museum Black
> in a 9500 - sometimes by a wide margin. Photo Rag gets to 1.74 with
> Ebony when it only hits 1.66 with Museum Black. That same 7500/Ebony
> seems to produce the overall better black with the matte papers - though
> not always.

Antonis,

For what it is worth. On my Epson 9000 I have replaced Ultratone 
VM set so the four greys are now in the Cc Mm channels. With the 
Eboni in the Magenta head I get a max density of 1.69 while it 
achieved1.61 in the Black head.  Both of Photo Rag and linearised 
with the Wasatch SoftRip.  So within the same head assembly of 
one printer a difference of 0.08 D can be possible. The densities 
were measured by a SpectroCam, T status.  That instrument isn't 
very accurate at the highest densities and the actual differences 
are probably higher.

I'm not sure about the following but it may be of interest: you 
mentioned the maximum inkload that will deliver the highest 
density and no gain with more ink above that point. (Analogue to 
the issue that is discussed quite frequently in the colorsync 
list when maximum gamut possible with profiling is discussed, 
there's no gain above a certain inklimit especially with pigment 
inks. )  With the other ink distribution on the 9000 I also think 
that a boost of the next grey ink on the black also depends on 
which channel is used for the black and the grey. My guess is 
that the Black channel lays down the last ink layer and when that 
ink isn't black ink like in my case the next grey will be on top 
of the black and the density drops. The pigment in that grey is 
not the Eboni kind and gives more reflection than the Eboni 
pigment. If I measure the unlinearised BO greyramp of the Eboni 
then I see no Dmax drop at the highest inkload.

Ernst