Digital BW, The Print

I can't speak for the HP, but with Epson drivers and 3K with and without PK
on matte, my experience is that while it's definitely not necessary for
smoothness, a small amount of PK can improve things, including by lowering
the amount of color inks needed to neutralize the carbon, due to the denser
PK printing more neutrally than the LK.

Paul
www.PaulRoark.com 


>There is this debate going on that when the Z driver adds 
>the PK ink to the MK rag paper output (quad as apposed to 
>Tri black) that you're not really gaining anything, and 
>could possibly even create a very difficult mix to linearize, 
>given the unequally spaced density dilution of the Pk ink 
>in a Quad set up like that.


>>In ABW 
>> mode of the HP driver the inks used in the neutral setting 
>> are either 4 or 3 monochrome inks for matte and 3 inks for 
>> gloss