Digital BW, The Print

Excellent. And interesting approach to the problem.

I stand corrected.
--
Bruce Watson



Paul Roark wrote:

> Bruce,
>
> > ...Please correct me if I'm wrong here:
> >
> > The UT7 inkset appears to have two toner sets - three cool (cyan) inks
> > and three warm (magenta) inks with a common black. Basically two
> > quadtone inksets used together. It gets a neutral tone by mixing the
> > cool and warm together. This is true, yes?
>
> No, to simplify, with respect to making neutral prints the variable tone
> inksets have 2 "channels" -- one pure carbon warm and one carbon with 
> "blue"
> pigments mixed in to make the ink cool.  (The mix that goes into the 
> "blue"
> toner varies -- basically cyan and magenta or R800 blue.)
>
> What is important to note is that the warm channel is pure carbon -- no
> color pigments at all.  It is not a "magenta" channel.  Actually MIS 
> carbon
> is essentially a low gamut yellow.
>
>
> > That the cool ink is cool means that it has a higher percentage of cyan
> > pigment ink than the more neutral K7 does.
>
> Yes, but the color is not just cyan.  It's blue (a mix of cyan and magenta
> or blue).
>
> > The warm side is similar - it has a higher percentage of magenta pigment
> > than the K7 does. It has to to get the warmer tone.
>
> No, this is where the misunderstanding is.  The warm side is pure carbon.
> Thus it has less color pigment than a neutral monotone inkset.  The mix of
> the cool and warm channels simply brings the total carbon-to-color pigment
> ratio to essentially the same as it would be if the mix was uniform in 
> both
> channels.
>
> Having a pure carbon channel has been one of my design criteria, because I
> want the ability to print a good pure carbon image.  For old photo
> reproductions they look great and are the most lightfast.  So far, 
> carbon is
> the champ when it comes to longevity.  So, a pure carbon channel has been
> one of my bottom line requirements.
>
> > These two inks, warm and cool, are then mixed on the paper to get the
> > tone you want. This is how it works, is it not?
>
> Yes, that is correct.  But the warm channel is pure carbon -- no color 
> pigs.
>
> I hope this helps clarify the comparison for you.
>
> Paul
> www.PaulRoark.com