On Dec 10, 2003, at 7:13 AM, Marttila Jouni wrote:
Hello!
Here is an example connected to this discussion. I have compared
ECI-RGB and
Adobe RGB with CMYK output profile (this has been made on sheet-fed
press
using quite high print densities to get wide gamut).
I have taken out two examples on different L-levels. On L 43 CMYK
profile
exceeds clearly Adobe RGB on magenta shades (almost ECI also) and
especially
on higher L-level CMYK exceeds Adobe RGB on yellow areas but is still
inside
Eci-RGB.
I don't know if this is correct way of looking - please correct me if
I am
wrong. However it looks like when using special printing condition
meaning
high print densities ECI-RGB seems to be better choice than Adobe.
Well yes if you're going to print just a bunch of solid patches which
were originally RGB, I have no doubt at all that you'll get better
results using ECI-RGB. But how many people are printing millions of
impressions of calibration/profile targets and getting paid for it? No
one. A far more practical test involves taking a series of digital
captures (originals) and converting each to ECI-RGB and then go back to
the originals and convert them to Adobe RGB. Take each set (Adobe RGB
and ECI RGB) and convert to CMYK. Now print them out and see what you
get.
If you're going to take a given set of RGB numbers and merely assign
ECI-RGB, then convert to CMYK; go back to the same set of RGB number
and assign Adobe RGB and convert to CMYK, then sure the ECI-RGB will
invariably look better (in terms of saturation). But those colors that
exist in ECI-RGB but not in Adobe RGB but could be printed (especially
to a press) are not very common.
And for image editing, it's like looking through a tunnel because
there's a considerable amount of color that exists in ECI RGB that
cannot be displayed on a CRT or LCD.
Chris Murphy
Color Remedies (TM)
www.colorremedies.com/realworldcolor
---------------------------------------------------------
Co-author "Real World Color Management"
Published by PeachPit Press (ISBN 0-201-77340-6)