Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@y..., "jrandall1149" <jrandall@c...> wrote:
> Alex:
> 
> Good, we are making progress.  Overall, what is your purpose/goal of 
> doing these experiments?  Where are you going with this?  Are you 
> trying to develop from scratch an inkset that will create smooth, 
> full range grayscale prints using only the Epson driver?
>

Yes, Jeff, or at least get closer to the proper grey mix rather than try to do all the recorrection of the inkset with software. From a microscopic view of the 21Step chart, it appears that the Epson driver uses the PC and PM inks to about the 45% level and then to the C and P for darker shading, the B becoming significant above 75%, with the C predominant from 35%-65% and M from 65% to 90%. The Epson driver thus uses the M position for the darkest shading.
 
> 
> Ok, you printed a 24-bit grayscale image.  What inks in what 
> positions did you use to print the 21-stepwedge?  What Epson dialog 
> settings did you use (Color or Black, Color Correction On or Off, 
> what printer profile, etc.)?  

Epson setup : Color mode, Correction Off, default ICM, Stock Epson 2000P Color Inkset. I have yet to fill the CIS carts and install them - 


> NOTE: Without applying a partitioned curve to a 24-bit BW image or a 
> lumped/non-partitioned curve to an 8-bit BW image all you are testing 
> is how the native, uncontrolled Epson driver responds.  Of course it 
> will yield strange results.
>  

I am lost in lumped partition workspace - very unfamiliar with these procedures.


> 
> Very interesting procedure.  How the inks on paper reflect light to 
> the eye might be better quantified if you p
> 

'p' print ??? I can't print until I install the inks, and I will do that only after I choose their positions. I am sure there is some non proportionality between dilution density and printed grey level.

> 
> The actual *color* Magenta may be darker (less luminious) than Cyan, 
> I have not done the experiment.  However, the current ink positions 
> of FS, FS-E, & PiezoBW are a historical artifact based on the 
> original positions chosen by the developers of the PiezoBW driver who 
> totally bypassed the Epson driver.  In reality, the inks can be in 
> any position (eg., either yellow or photomagenta position could hold 
> the darkest ink) if the driver is written correctly.  When MIS 
> developed the FS inkset they wanted folks to be able to use the FS 
> inks with the PiezoBW driver.  Because many folks wanted to also use 
> the MIS inks with Epson drivers, a series of partitioned and 
> lumped/nonpartitioned curves were developed to control the Epson 
> driver with the inks in the historical positions.
> 

I am going to try to do this with the Epson Driver as there are no alternatives (aka Piezo) for the 2000P. I had fully planned to stuff this printer in the closet and purchase a 1280; this is a last attempt at making my 2000P work before doing so. 

 
> 
> 
> Many folks are using the VM and FS families of ink with an Epson 
> driver quite sucessfully and producing smooth, nonposterized prints 
> with the currently available workflows.  The partitioned workflows 
> have been especially written for the current ink densities and 
> *color* positions.  There may be mislabeled bottles or incorrectly 
> filled carts, but there are no 'misplaced' inks.

I tried a set of VM prefilled carts ( for the 1280 ) and was not pleased at all with the results. I tried Paul Roark's color correction curves, but never got satisfactory results - the prints were highly posterized..
 


Regards,
Alex