Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "mike_nunan"
<mike_nunan@h...> wrote:
...
> Tyler, in your reply you mention partitioning in the driver. I 
> haven't heard the term used in that context before, what does it 
> mean? Is it the proportioning of the inks according to a set of 
> crossover curves?

Essentially yes. I haven't been keeping up on all new developements
but these are the methods I'm aware of-

Editing a file converted to color to control individual inks-
Paul Roake's and others RGB curves, also can be done in CMYK with a
RIP, Conetech ICC profiles (essentially doing the same on the fly).

Driver partitions inks on the fly from a grayscale file-
ImagePrint in Quad mode, StudioPrint, QTR, IJC, R9 plugin, Pro24RIP,
Septone system.
Of these, ImagePrint, R9 plugin, Pro24RIP, and Septone system are
preconfigured to do this for you and use supplied profiles for
specific inks and/or media. No user controls for the specifics of
partitioning, but considering many user's great results this may not
be a drawback for most users. Others find canned approaches a major
drawback.
StudioPrint, QTR, and IJC on the other hand give a great deal of
control to the user for partitioning and allow hardware linearization.
The advantages are that many inksets, papers, and approaches can be
utilized and brought to a linear state to specifically meet the user's
needs. I haven't worked with IJC, but with the other two you do not
specifically work on curves, only set parameters that are in effect
like applying curves. The downside is that some knowledge and
experience are required to get results that equal or exceed some of
the preconfigured options. It should be mentioned that StudioPrinbt
will require some very creative thinking, profiling, etc. to use
monochromatic aproaches that are not straight quads or quad blends.

> Regarding the rest of your post, you seem to be 
> saying what I thought, intuitively, must be true: there is no reason 
> why a UT7-based setup should be especially "dotty" compared to the 
> quadtone Studio Print system.

I'm not familiar with the UT7 system, but you seem to be grokking this
whole deal so I suppose so. Keep in mind there are issues besides
partitioning with some of these advanced RIPs, dither and pass
functions that effect results. But everyone knows Epson's screening is
great.

> Ok, you lose a bit by having three rather than four tones, but with a 
> suitable driver and avoiding the toner inks, there's no reason why a 
> print created on a 2200 using Paul's workflow shouldn't be very 
> smooth indeed. Of in practice the Epson driver might well NOT be 
> doing the "right" thing -- anyone know from firsthand experience what 
> the case is? Steve M, if you're reading this would you care to 
> comment?

Others, like Paul, who have put more time in on this should respond. I
can say from my own many hours of working with RGB curves and the
Epson driver that it is ill suited to the task but can be tamed. I've
seen spectacular results from the Conetech 1160 icc profiles that
prove the point.
I hope there is no misinformation about particular products in the
above, please correct me if so.
Tyler