Roy,
Thanks, I can see how attention to crossovers and associated densities during profile development can help with the issue. Your discussion reinforces the point for me, thanks.
My inks are in transit, so I\u2019m doing the mental prep in anticipation. I did quite a bit of learning while working up curves for UC on Kirkland, so I think I\u2019m ready to dig in.
Best regards,
John Moody
-----Original
Message-----
From: QuadtoneRIP@yahoogroups.com [mailto:QuadtoneRIP@yahoogroups.com]On Behalf Of Roy Harrington
Sent: Friday, August 26, 2005 1:48
PM
To: QuadtoneRIP@yahoogroups.com
Subject: [QuadtoneRIP] Re:
Improving Dither
--- In QuadtoneRIP@yahoogroups.com, "John Moody"
> Can
profiles affect dither patterns in any large way? I'm talking about
> tweaks to
one profile, not profiles for different papers, inks, etc.
> Soon, I
will be spending significant time creating profiles for a modified
> UT7 set,
and if there is a way to improve the dither pattern I would like to
> incorporate
that.
>
> I'm
currently printing with 2200 UC inks on EEM.
>
Specifically, I see sparse dark dots in the ¾ tones that I do not see when
> printing
through the Epson driver. By sparse, I mean there are maybe 10
> dots
between the dark dots. Printing modes are,1440 super on QTR better
> speed, 1440
no-high-speed on Epson driver. QTR is far superior in every
> way, other
than dither patterns. I would like to find a way to do better.
>
> Best
regards,
> John Moody
Hi John,
The way
dithering is done is pretty much fixed -- unaffected by the profiles.
However the idea
behind partitioning multiple gray inks is to hide the dithering
so you don't see
it. So in this sense the profiles can make a difference in the
visibility of
the dots and dithering.
I'm guessing
what you are seeing with the dark dots in the 3/4 tones is simply
the transition
from light-black ink to black ink. It has to happen sometime.
The idea of
partitioning is to introduce black only when the light-black is close
to full so you
see K against LK rather than K against white paper. Does this sound
like what you
are seeing? If the black dots are sparcely separated that's the idea
of
dithering.
When you print
with the Epson driver more inks are used so the hiding of dots is
better but of
course this is what introduces metamerism.
When you go to
UT7 things are a bit better since there are 3 grays rather than 2.
Quad systems are
very smooth and the ultimate is Cone's new K7 with 7 grays.
Roy