Daniel Magee writes in regards to the ECI Coated CMYK profile:

>> There are thousands of scanner operators and CMYK retouchers who believe
that in order to get a neutral colour your cyan should be higher than your
magneta and yellow AND the magenta and yellow should be equal.Every day
these retouchers and scanners base their corrections around this fairly
fundamental belief, a belief wrote about by Dan Margulis and many more I'm
sure. <<

Yes, anyone who regularly deals with CMYK comes to know that this is a
device gray balance and that it is not linear from highlight to shadow and
that it is device dependent.

If working direct in device space (CMYK) then one will have to know about
gray balance and how to achieve it over the entire tonal range. These folk
often know the output well, so they may have 'hard wired' numbers which they
aim for for a neutral tone at the desired brightness level. In these
situations, having an idealised aimpoint simply works well for colour
correction and with the separation aimpoint in mind (probably a proof rather
than press) then the colour build may be neutral or it is not going to
matter too much on press with minor tolerance differences.

In the darker tones, neutrality issues are less of a concern than the
lighter tones.


>> If you create an RGB file with R0 G0 B0 and proof it with the ECI profile
"IsoCoated" you will see that it reads cyan 87, magenta 86, yellow 76 and
black 99. <<

Yes.

I have made this point many times myself on other lists - but I get the
feeling that my point may be lost or not fully understood.

If the numbers in the file and the ICC profile which will be
assumed/presumed/assigned do not make zero AB values - then things will not
be truly neutral.

This may or may not be an issue - depending on the workflow. Those that use
'hard wired' aimpoints would/should not care as long as they hit their magic
numbers. Those making more use of ICC profiles in their work and proofing
and output should base their 'magic numbers' on the profile which describes
their device - rather than using a legacy hard wired idealised
aimpoint...otherwise the profile tends to become meaningless as the true
description of the files numbers.


>> To all these retouchers this would suggest that it is going to come out
with a magenta bias. Therefore they would correct for that to make the mag
and yellow match. <<

Yes, see above.

Those in the know probably would not do this...but this means using the
numbers indicated by the profile as the aimpoint - rather than some numbers
gained in other ways. Using a profile as reference means that one does not
have to remember crazy ink builds which is probably why idealised builds are
common.


>> Many would also look at the black and say that 99 percent is too high and
would not be happy at all about having to use this profile. <<

Agreed, not to mention the long black plate with K kicking in in the very
early quartertones.

And the big contrast kick in the perceptual intent is a pet hate of mine -
Adobe do not do this (which I am thankful for).

I don't know how many 'average' users would even know or care - they may
just hit the CMYK button and never look any further. All one has to do is
produce a perfect 16 bit wide gamut RGB and convert to CMYK, don't they? <g>


>> If you compare it to "eurostandard coated" which ships with Photoshop the
same R0 G0 B0 converted to CMYK reads C95, M83, Y82 and K90. This would be
considered far more acceptable. <<

Different colorimetric data though, so that is why the ink build is
different to produce the neutral tone at the required darkness level.

Yes, this is a good example of how to offer a boring but safe profile -
IMHO. Credit to Adobe for this move.


>> I don't have the Cromalin Eurostandard DP10 profile so I can't say what
thats like.My point is that if Proof4Press comes out with a profile with
dark neutrals that are similar to the ECI profile then so be it but they had
better be ready to re-educate thousands of scanner operator and retouchers
and fight some pretty big battles on the way. <<

Yes, it would appear that fun times are ahead for users adopting this
aimpoint.


Regards,

Stephen Marsh.

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