--- In colorvision_group@yahoogroups.com, David Miller <dm2363@...>
wrote:
>
> >
> > I used PhotoShop to Soft Proof the adobe church using 5 profiles
> > (PrintFix Pro 225 and 225 with grays, Ilford profile for R1800 and
> > their Pearl paper, Epson's profile for their glossy Photo and a
> > Profile Prism profile for Epson glossy and the R1800). All
profiles
> > show the blotches in the sky but at different places. The Printfix
> > profiles show the blotches at the top and across the crosses
> > depending on the intent. Other profiles are at different places in
> > the sky. Darkening or lightening the sky moves the blotches up or
> > down but does not completely eliminate them. I think this is just
a
> > tough test for any profile; I have not printed the church so I
don't
> > know if it's visible on an actual print.
> >
> >
>
> Try printing and measuring 729 patches, and use those colors in
> combinations with your grays measurements. I've done some recent
> testing and closer evaluation of the R800 (same inks as yours, just
> smaller paper) and it really needs the extra patches to avoid
problems
> in certain areas; the R800/R1800 is tricky to profile with fewer
patches
> because of its inkset (the extra red and blue inks) and what I found
> is that with 225 patches, I was getting too much saturation and some
> loss of smoothness in faces.
>
> (this was on both Premium Luster and Harman Gloss)
>
> So from now on, I'm using 729 patches, always, for the R800, and
I've
> also done a similar profile for the Canon 9500, also on Harman
Gloss,
> with 729 patches plus 238 grays.
> >
>
> David Miller
> Senior Software Developer, Digital Color Solutions
> Datacolor
>
Hi David,
Thanks for getting back. I built a new profile using the 729 patches
with the grays as you suggested. I did not see much difference
between the profiles using the PhotoShop soft proof. So, I decided
to quit pixel-peeping on the monitor and I printed the church on the
same piece of paper (Ilford Pearl) using the Colorvision profile and
the Ilford profile. Looking with a magnifying glass and good light I
can not see the blotches in the sky (the prints are smallish, about
3x4). The only differences between the profiles is the Ilford profie
produces a print that is a little brighter and a little bluer in the
sky, the Colorvision sky is a little towards purple but still blue.
The biggest difference between the two is in the lower level
doorway, The Ilford profile is a little lighter in this area and
shows a little more detail. I may redevelop the profile using some
of the advanced adjustments.
It's also possible that I'm bumping into a monotor limitation. Using
Photoshop's colorpicker there is only a difference of 1 in the blue
value across the area that is blotchy.
One possible suggestion for Colorvision. If Epson printers produce
targets that are so dark that they are hard to profile you may want
to consider making a "bright" target. The software could be adjusted
to compensate by knowing that the target was "bright" and the color
readings may be improved. I noticed that some of the dark areas on
the targets were very dark to my eye and showed a large difference
between the reading and the ideal.
Thanks for your help.
Bob Schoner