Digital BW, The Print

"sevendaysprinting" <destudio@...> wrote:
>
>...we have an Epson R2400 with CIS system (Lyson), replaced the black inks with HP Photo Black + Grey + Light Grey (Z3100) in order to achieve more neutral toned black and white prints. ... mainly PK printing.

> I have 2 problems:
> 1. printing through QTR RIP and using solely the 3 black (HP) inks without toner colors, we did notice quite some copperish, reflective "bronzing" with these HP Vivera carbon black pigment inks on our satin papers. This is somewhat a bummer.

Gloss optimizer helps but is less than a perfect solution.  Spraying the print later is more effective but not a step most like to take.

I've found that PK black only bronzes less.  You might try a profile with low ink limits on the midtone inks.  See if that helps.  You might end up balancing smoothness against bronzing.

MIS's use of a coating in the base as opposed to on the individual particles also results is less bronzing.  In fact, diluting HP PK with MIS glop resulted in midtone inks with lower bronzing.

> 2. using Epson's driver in ABW mode, we achieve a nice screening and no microbanding but we do not manage to print with only 3 black inks without toner colors (not in ABW, not in Black Only) whereas printing with QTR (in ordered and adaptive hybrid mode) does print 3PK only but gives a lot of microbanding: mainly in the first and last printing lines.

Three inks is marginal in some printers, and most of the modern printers seem to need both rollers engaged to get the best paper transport.  The Epson dithering pattern as well as more inks firing seems to hide the problems more effectively.  I use wider top and bottom margins for most prints now.

Paul
www.PaulRoark.com