Has this ever happened to you before? You’ve
designed a beautiful color print job consisting of photos, illustrations,
and text matter. A veritable feast for the eyes, which not only jumps
off your screen in brilliant multi-color hues, but also looks simply
scrumptious when output to your desktop printing apparatus, whether
it be laser, inkjet or some other technology. Yet after it’s printed
and delivered, you’re not happy with the color! As a matter of
fact, the final product does not even come close to matching the color
visual you supplied, the item that you based your color expectation
on.
What went wrong? Well, to answer that question all we need to do is
understand the correct and incorrect color modes. So, let’s start
by examining these key color issues which, when understood, will help
customers avoid the dreaded “this color is way off’ phenomenon.
Incorrect Color Modes
The
primary concern, when designing for color printing, is that we use the
correct color modes. For professional print publishing the two accepted
color modes are CMYK (Cyan, Magenta, Yellow, Black) and SPOT (PANTONE,
Toyo, etc.). CMYK and SPOT colors aren’t just preferred by the
printing industry, they are required by the printing industry. The reason
is simple, really. Because printers print in CMYK or they print in spot
colors. Other color modes (Index, LAB, etc.) and especially the ever-dreadful
red, green and blue (RGB) are not acceptable color modes for printing.
Files supplied in any color mode other than CMYK and/or SPOT color must
be converted by the print vendor before output can occur. It is during
this conversion that color shifts commonly occur.
When “other” color modes are converted to CMYK/SPOT, the
contractor’s prepress workflow does it’s best to, for instance,
convert the RGB blue from Word to a comparable CMYK blue. The problem
is that CMYK/SPOT can only achieve about 6,000 different colors while
RGB can achieve millions. This is called “gamut,” or the
amount of colors that can be produced. To output from RGB, a contractor
must literally convert colors from a system with a gamut of millions
of shades of color and squeeze that down into a manageable 5,000 to
7,000 shades of color (what the press can reproduce on paper using CMYK
inks). What is lost is often the bright, vibrant color that customers
want. To better illustrate the concept of “gamut,” consider
that you, as the creator of your colorful publication, are using a box
of crayons. Your box contains an assortment of 128 delightfully named
sticks of color (sunburst yellow, oceanic blue, show me the money green,
etc.). Using all of your crayons, you create a colorful drawing and
then pass that drawing to a vendor to make 5,000 copies. Now our vendor
is sitting there in his/her plant holding their box of crayons, and
I might add that this box only contains 16 crayons (yellow, blue, green,
etc.). Clearly, something will be lost when the vendor tries to reproduce
your work.
Take
a look at this example of an RGB image versus it’s converted to
CMYK counterpart:
RGB
Mode Image |
|
| |
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CMYK
Mode Image |
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So
what do you think? Is a contractor going to match your RGB creation?
Not likely. Can a vendor ever match your RGB color files? It’s
possible, if you furnish a color visual and if you specify that the
color visual is for color match and if the specifications include the
fact that the visual is for color match and if you don’t mind
paying for additional system work to color correct your files and if
the vendor is technically competent (boy, is this a bunch of ifs). Then,
and only then, might you get a product that is a close match, not an
exact match, but a close color match, of your intended product. Working
in RGB is iffy.
It
should also be noted that customers should - “beware” of
the color visual. Desktop printers (Laserjets, Inkjets, etc.) utilize
toners, dies and inks, which are very different from printing inks.
This difference causes color expectation problems. Then throw in the
differences in paper stocks that you use in your desktop printer and
how they differ from a vendor’s printing papers and you have a
recipe for “color shift soufflé.”
Correct
Color Modes
This section of the article is called “correct color modes”
because the modes of color we will be discussing are industry standards.
They can be evaluated using many different guides, with one of the quickest
and easiest guides being PANTONE swatch books. The swatch books contain
actual printed samples of the color and can show you a spot color or
a process build with the actual percentages of ink used to create the
solid. These guides can help you create the color you are looking for
while still using one of the correct color modes.
But don’t be fooled into thinking that simply using the correct
color mode will make your product right. Sometimes when we work in the
correct color modes and use the aforementioned guidebooks, we still
get a shock when we see the final printed results. For instance, lets
say we create a file and decide to use a myriad of spot colors, I’ll
pick a number out of thin air, let’s say nine spot colors are
used for our document. Our document is large, 244 pages, and spot colors
are used throughout all of the pages (headers, text matter, line matter,
etc.). The combination of 9 spot colors and 244 pages makes our publication
cost prohibitive. Why? Because running 244 pages in 9 colors is very,
very, very expensive. So much so that the logical solution is to minimize
the number of colors used, and we can do that by converting the 9 spot
colors to CMYK. So what do we do? We convert our files to output as
CMYK, and our job now prints 244 pages with only 4 inks. Better, but
here again a conversion is required and because we must now build a
single ink color out of what could possibly be a total combination of
all four process inks (cyan, magenta, yellow, black), - chances are
pretty good that it’s only going to be a close match.
Take a look at this example that shows PANTONE spot colors along with
their converted to CMYK brethren:
Proofs
Color expectation now comes full circle. What better way to truly evaluate
the color that will be produced by the print vendor, then to have them
supply you with a contract color proof (meaning a proof which can be
used for color match on press). In most cases you can’t judge
how your color files will image, especially if your using an incorrect
color mode. So a proof is going to save you from looking at a printed
product (such as our example of 244 pages and 9 spot colors) only to
discover that it doesn’t meet with your color expectations, and
now it’s to late to make necessary changes to the file, so your
left with the decision to accept an inferior color product or pay to
have it color corrected and reprinted.
A
contract proof creates a color standard for the vendor to follow. If
the printed product does not match the furnished color proof, then it
is a much simpler process to require the vendor to make the requested
color changes. By giving us a contract color proof, the vendor is stating,
“This is what I can match on my press,” if he doesn’t,
then shame on him.
So,
what does all this mean? Well first and foremost, use proper color modes
(CMYK or SPOT). Secondly, don’t expect your color visual to look
like the final printed piece – too many variables. Thirdly, use
swatch books such as PANTONE’s color guide systems to determine
color – don’t depend on your computer or the corresponding
laser printer. Finally, if all else fails, refer back to your contract
proofs – they can be a job saver.
Having read this article and fully understanding the differences and
limitations of the printing process when it comes to color, we are all
going to adjust our preconceived notions on how our color files will
output when sent to a professional publishing establishment. Right?
The only other option is that we as customers decide to continue with
the status quo of color expectation. In that instance, we must be prepared
to be disappointed repeatedly when it comes to our color expectations,
especially if we are not using a standardized color mode.
