QTR-Quadtone RIP

As folks have noticed, "black" inks are not black, and all by themselves 
produce a tone that is decidedly warm, even "brown." -Theoretically- CMY 
= black... but in a real world case, it doesn't, hence the K.

In order to get a reflected-light black, from inks that produce a 
brownish tone, one has to add cyan. That provides the "cold" neutral to 
shades of gray.

I just went thru the process of linearizing the standard K3 inks using 
Richard Boutwell's system, and ending up having several email exchanges 
with him. I was trying to get my 9890 / K3 to give me the same (or as 
close as possible) visual sense as my 3880 which uses Piezography, 
including the (rather amazing) HD black ink.

It was all decidedly warm until I added in the cyan, and messed with the 
percentages. (I did come pretty close, eventually, although certainly it 
leaves much to be desired when viewed side-by-side with a "real" piezo 
print..)

So, IMHO, hand-wringing about the microscopic inclusion of yellow or 
cyan (which I'll easily admit I did myself, years ago) to create a 
visually pleasing black/gray is confusing the theoretical with the 
practical.

Look at it another way: Red isn't "native" either in CMYK printing, and 
no one seems to mind the inclusion of other colors in the magenta ink to 
achieve it.

Tracy
www.valleau.art