Re: The Color of Green?


Lee Varis
 

Steven Writes:

it is perhaps possible they scanned as RGB and
separated in APS using custom CMYK set to UCR/Lt GCR with an ink
limit that was indeed this high...I would guess that these are drum
separated scans (probably a prop. sep. table).
Yes, this is my guess as well – I also think Dan has it it right in the
head below –
Dan writes:

The files are obviously untagged when
scanned, then the printer opens them up in Photoshop, clones out any
dust,
hairs, etc., and resaves them using a color setting that unbeknownst
to him embeds
an irrelevant profile.
Steve writes:

Do these images have the legacy profile tagged and you are just
seeing how another preview of 'SWOP' compares, or are these files
untagged and you are attempting to see what would suit them as a
description?
They mostly have this mystery "SWOP (coated) 20%" tag though some have
no tag which suggests to me, as Dan says above, that they were probably
Drum scans into CMYK and originally didn't have any embedded profile.
The wrong profile ended up there after spot knocking, the files that
didn't need any dust removal didn't receive the bogus profile. Come to
think of it, the printed press proofs supplied as patch color look a
bit better than the screen previews through the profile supplied – that
makes sense as these files are destined for a sheetfed press not a web
press!

Again Steve writes:

What seems a safe TIL and K to you, since you know the stock and can
see a general aim print? Is 300 too light and 330 a good middle
ground to edit or re-sep to? This has often worked well for me in
coated magazine publication quality type conditions where I knew that
I could use more than 300 but did not wish to go to 360.
This is kinda what I was thinking. and as Dan writes:

But in any case, I would be more conservative, because if you
assume the best and it turns out not to be so, the job will crash and
burn,
whereas if you assume the worst and it turns out better than what you
had hoped,
you're not badly off.
So...

The more important shadow detail is to the picture, the more you add K
and
subtract CMY.

As for the greens of palm trees, the very bluest ones will have C=Y.
The very
yellowest will have (Y-C)-(C-(M+K))>=0.
LOL, Dan, I was hoping I wouldn't need a calculator for number
suggestions – can that last bit be expressed in a simple ratio? I was
thinking something like 1.5:1, Y:C or can I let Y go higher?

To increase the saturation of greens in a CMYK file, try Channel
Mixer>Magenta=Magenta 130%, Yellow -30%. You may need to do this on
a separate layer in Color mode.
That's exactly what I was looking for!!! I'm used to doing this in RGB
with +G and -B. It works like a charm in CMYK! Excellent!

And finally, Dan writes again:

As drum scans, these have presumably been sharpened already. However,
palm
trees are a difficult sharpening case because their narrow leaves
often aren't
fully resolved. Wide semi-haloes are often a good solution. So, try
(in CMY
only, not K) sharpening at Amount 60%, Radius 10.0 pixel, and see if
you see any
improvement, understanding of course that you can probably find better
numbers if you work at it.
They have been sharpened – some more than others and some even too
much! I'l give your suggestion a try on the less aggressively sharpened
ones though I'm inclined to leave well enough alone on this.

Thanks so much for this advice! I have one more question for you all.
SHould I leave the profile that is embedded with these files (since
that's the way they come) or would it be safer, since this is probably
not a real profile, that I just return the finished files "untagged"?

Please bear in mind that this IS NOT an opportunity to educate a
printer on the benefits of proper profiling.

I'm just wondering if I should leave the existing profile on the theory
that it may be there for a reason even though the profile is "named"
SWOP (coated) 20% , we are printing sheetfed and the actual numbers in
the file suggest that they are prepared with the higher TIL of the
sheetfed press in mind.



regards,

Lee Varis
varis@varis.com
http://www.varis.com
888-964-0024

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