Digital BW, The Print

wifflebomb wrote:

> I agree it is some kind of "ink starvation" and that the driver needs 
> to be telling the heads to spray more ink on the darkest tones 
> somehow.
> 
> This leads me to another question:  what good are paper profiles when 
> you are doing Black Only?  Don't all canned profiles calculate the 
> amount of ink being sprayed on the assumption that all 7 inks are 
> available and mostly spraying along with the black?  Has anyone 
> made "Black Only" paper profiles, i.e. profiled on the premise that 
> only one head is spraying with black ink?

Black Only paper profiles would ask for another profile creation. 
One way would be a "none" profile that gets PS curves implanted 
for linearising the density. However I doubt BO printing uses 
profiles at all in the Epson driver. The internal paper settings 
data will be used but can't be changed. So PS curves are the only 
option I guess other than using non-Epson drivers.

Though I'm not using BO printing at this moment I've raised the 
question before whether BO printing could become better if the 
black wasn't just squirted from one head but say 2, 3 or 4 heads. 
That means dedicated cart(s) and a driver that can reduce the ink 
amount per head by the number of nozzles extra used. It is not 
that I believe that it is impossible to do it with one head but I 
very much think that consistency in the print and in time could 
improve a lot. The C84 (all the nozzles available) or the R800 
for the desktop given their small droplet size. The 4000 would be 
the easiest if both black heads can be used simultaneously, 
that's 360 nozzles together. The smallest droplet sizes possible 
in a given printer will be used when the heads are limited in 
throughput. That's 1.5 picoliter for the R800 and 3.5 picoliter 
for the 4000, the C84 falls in the last category if my memory is 
correct, Depending on the limitation and the range of droplet 
sizes available the next one above the smallest size may appear 
as well in the shadows. This most likely will require the use of 
QTR and possibly a bit more hacking in the Gimp-print origins to 
get the best of all possibilities.

Ernst