Re: Calibrating and characterizing ABC
Re: Calibrating and characterizing ABC
- Subject: Re: Calibrating and characterizing ABC
- From: Henrik Holmegaard <email@hidden>
- Date: Wed, 10 Oct 2001 09:39:05 +0200
Steve wrote:
Calibration is a scanner function and should be documented in the scanner
docs.
I totally agree.
Hmm...I don't -:).
The first thing you need to know is if the calibration is automatic
or manual. And if it is manual, then how often to calibrate.
A Heidelberg scanner will flag you, if the lamp is off. A
Hewlett-Packard printer will flag you, if the densitometry lense is
dirty or there is some other reason calibration can't be completed.
To be honest I don't know what an Apple monitor does, if it can't
complete it's internal calibration, maybe John Gnaegy can step in
here?
The X-Y chart scanning iCColor has auto-calibration. It doesn't ask
you to do anything, just like the printer and the monitor and the
scanner don't. The important point is that calibration works ...
every single time and every day of the year. No lunch break, no
mid-afternoon coffee break, no break at all in fact.
Preferably you don't have to do anything to activate calibration, but
it does something to activate you in the event that the device fails
to meet its target state.
The second thing the user needs to know is that a calibration and a
characterization are quite different things.
The studio printer (and the studio monitor) are your basic means of
simulating other hardware configurations, whether you aim to use them
on a different site or on a different schedule. They are like magical
binoculars, they let you see what will happen far away, and even at a
later time -:).
Therefore, the task of testing alternative characterizations serves
to optimize the color space of the two primary simulation hardware
units used to judge color. These units must be optimized not just for
device stability, but for size and shape.
If the monitor is old, it will have a loss of size in the blue region
(if you drove it at +5K) or the red region (if you drove it at 5K).
You can only throw it out and buy another.
But with the studio printer you can and should look for alternative
papers and maybe inks. There is a vast difference in gamut as between
inks and papers for the same printer.
And this is where you want to use a gamut comparison tool. Because
while you are still setting up the studio printer, you should review
its possible gamuts compared to the standards-based and custom output
profiles you and your workgroup normally use.
A gamut comparison tool does not help once you are in production. It
can't change a studio printer gamut that is inescapably too small (or
make a studio printer with wobbly stability all of a sudden stable).
Even if Roberto would like to maybe move the primaries around just a
bit ... -:).