Re: Approval and ICC
Re: Approval and ICC
- Subject: Re: Approval and ICC
- From: Chris Murphy <email@hidden>
- Date: Sun, 12 Nov 2000 01:24:44 -0700
Jim Mitchell <email@hidden> writes:
>
So Joe, your saying that good color or match color is a function of dot
>
structure,
>
screening, rotation, rosette and density.
No I think he's saying, Kodak would say, and I'm saying that a digital
dot contract proof by definition shows accurate dot structure, screening,
rotation, rosette. I wouldn't include density because that is dependant
on the difference between proof and press inkset.
>
Approval is a great machine but because of the
>
different
>
colorants used in proofing systems and printing systems, using an ICC
>
profile is
>
the best tool available for achieving the holy grail of match color.
If you have to use ICC profiles for cross rendering, to get the Approval
to show you what your press behavior is, then a.) the Approval isn't set
up correctly; b.) the Approval isn't an appropriate proofing device for
your press.
Approval is a digital dot proof. If you profile it for the purpose of
cross rendering (to get it to simulate your press conditions, because it
isn't doing this on its own) then you *WILL NOT* be using it as a digital
dot proof. You will get dots on the proof you won't get on press and
that's not the idea behind the Approval system.
>
I'll take a false proof that has a better visual
>
match than an
>
accurate dot and density proof that doesn't match any day.
A majority of people who decide to use Kodak Approval are wanting the
dots. That's why they get Approval in the first place. If you don't care
about dots, and your customers don't care about dots, and the pressmen
don't care about dots - then don't worry about this thread.
Just realize that at some point you MIGHT come across a customer who sees
halftone dots on their proof and EXPECTS and might DEMAND that there is
reasonable comparison on press as well. If this happens, they aren't
going to be happy that the Approval was rigged to not provide accurate
dots.
>
In a few years most of us won't care about dots, well be going for a
>
visual match.
It depends on the job. Some people regularly print images that are prone
to subject moire. I know printers where this happens less than 1% of the
time. I know other printers where this happens more than 1/3 of the time
because they print a lot of catalogs containing fabrics (couches, shirts,
anything with a pattern in it). If you don't have an accurate dot for dot
proof, you might get really screwed on press.
Those companies going CTP have an easier time with this because they can
change screen angles and produce a new plate and get it up to density in
15 minutes - not a big deal. But not everyone has a workflow that allows
for this. So it's not fair to say no one is going to care about dots.
>
Now I do agree with Joe that every effort should be used to get as close as
>
possible by using density and dot gain.
If the inksets are different, density can be different while color is the
same. If I produce a color match on an inkjet and printing press, a
densitometer will NOT product the same values for those two samples that
LOOK identical. Density should be used for process control on the same
class of device, not for color comparison between device classes (or
inksets).
Chris Murphy