Long used to dealing with CMYK, artists are now
faced with varied output options. In this article, I
show how to cope with various file sources, color
modes, and output options while maintaining control
of your color throughout an all-RGB workflow.
Why RGB?
With today’s abundance of RGB source art such
as digital illustrations and photos, art is routinely
“repurposed” (redirected for different outputs).
There is great need for a flexible workflow and a
master image you can twist and bend to suit your
output needs. The RGB mode is well suited to play
host to these diverse needs, with its larger color
gamut and dynamic range (compared to CMYK).
In the following workflow, a master RGB image
is color corrected for and archived in RGB form.
From there, duplicates may end up as varied output
like a six-color poster, art for a website, or a small ad
insert. Regardless of output, you will be able to see
what a difference the process makes.
You will be relying on your monitor to make
critical color decisions, so it’s vital to calibrate and
profile it, and maintain its fidelity on a regular basis.
Managing expectations
The term workflow means different things to different
people. In this case, I’m referring to a pipeline
that produces consistent color at every stage. As a
content provider, you need to manage your expectations
as well as those of clients because “color
matching” is seldom that. Despite all efforts, colors
in final outputs seldom match originals exactly,
due to differences in media, inks, and technologies.
Since these factors may be out of your control, set
realistic goals and expectations up front.
1. Understand the goals.
Save yourself trouble by determining your client’s
color goals up front. Are you to match the original’s
appearance? Or are you to produce “pleasing” color,
where you’re free to alter colors and saturation?
Anyone with basic Photoshop skills could tackle
the latter. But matching an original accurately takes
skill. This is especially true in a complex system
involving diverse devices like scanners, digital cameras,
monitors, proofers, and printers—all of which
define and produce colors differently.
2. Use appropriate color settings.
It’s critical at this point to set up a suitable color
environment so that color management is fully
enabled. You can set up one application first,
then synchronize the others. I prefer to do this
in Photoshop. Type Command+Shift+K (Mac) or
Control+Shift+K (PC) to access Color Settings.
From the Color Settings menu, choose North
America Prepress 2 as a starting point.
You can customize this setting by choosing a
printer-recommended RGB working space. If your
printer doesn’t recommend one, try setting Adobe
RGB for photographic output or Colormatch RGB
for press output. The former has a larger gamut and
produces more saturated colors and sharper tone contrast.
The latter closely matches the typically compressed
tone and color range of an offset press.
If your printer has provided a custom press profi
le, load it as a CMYK working space. Click the Save
button to save the color setting with a unique name
and a “.csf ” file extension. This saves the file in the
correct location on your operating system. You can
also add a comment about this setting.
Tips:
- Create a custom setting for each of your workflows. Load the appropriate setting from the
Settings menu before you work on the project.
- Share the custom setting with others who will
view your art on their monitors. Your artwork will
look identical on their monitors, provided they’re
calibrated and profiled.
3. Assign source profiles.
In a color-managed workflow it’s vitally important
that all source art contains a profile. Documents
embedded with a profile are referred to as tagged
files (scanned art tagged with the scanner’s profile,
or digital camera files tagged with the sRGB or
Adobe RGB color space profiles). These tagged files
give your computer’s color management system valuable
information about the origin of the colors and
how they should appear onscreen and when printed.
Most quality scanners allow you to embed a
scanner profile if a custom profile has been created.
To assign a profile to a scanned RGB file that’s missing
it, or to add one to a client’s file with no profile,
choose Assign Profile from the Edit menu (Adobe
CS2 applications), or from Mode in the
Image menu (previous versions of Photoshop).
To ensure the colors in the file display correctly,
you can either assign a custom scanner profile
that you created with profiling software or assign a
standard RGB working space. (Try assigning sRGB,
ColorMatch RGB, or Adobe RGB.)
4. Evaluate images and assess changes.
You’ve decided on your color goals. Now you need
to see if the image can support the goals. You’ll
also want to consider the corrections the image will
require. Many designers keep written notes on corrections;
an efficient method is to annotate corrections
right on the image. Some tips:
- Add a new layer.
- Use the Pencil tool in a bright color and a bold
typeface to call out corrections.
- Use the Notes tool (N) to jot down overall color
correction goals.
- Save the file in Photoshop (.psd) or PDF format
with annotations and layers.
5. Convert to color space profile.
If the image needs much editing, I suggest you convert
to a “container” working space first (CS2 applications:
Edit > Convert to Profile; previous versions
of Photoshop: Image > Mode > Convert to Profile).
It’s not wise to edit colors in a device-specific
scanner profile, or even in the limited color palette of
the sRGB color space. Choose a robust and deviceindependent
color space like Adobe RGB (1998) or
ColorMatch RGB, which have the broad spectrum of
colors required for output. Choose Perceptual Intent
and check Use Black Point Compensation.
If you don’t need to edit the image, convert a
copy of the image to the final output space like a
custom CMYK profile for press, proofer, or a print
preset like U.S. Web Coated (SWOP).
6. Adjust tone and color.
Color management is not the same as color correction.
At best, color management means matching
the appearance of the original … but you may still
need to correct flaws in the original. The industrialstrength
editing features in Photoshop can help you
achieve professional results. Use adjustment layers
whenever possible to keep corrections flexible.
Color correction tip: Consider acquiring source
images at a higher bit depth than the standard 8
bits per channel, especially if the image requires
extensive editing. There is more data to manipulate
in an image with a higher bit depth, so there will
be less degradation once you’ve done your editing.
Duplicate the image and convert it to 8-bit mode
prior to printing.
7. Apply sharpening.
Now apply a pass of sharpening to the image. Many
experts feel a print workflow requires two passes:
one pass early on to compensate for slight softening
from the digital capture, and another at post-editing
to compensate for any fuzziness when printed. You
can use the Unsharp Mask filter or the new Smart
Sharpen filter (CS2) in Photoshop.
8. Proof!
An important component of a color workflow is
a hard proof (printed proof) to check print color.
Often a contract proof is signed by all to approve
color output; this is for matching color on press.
In an all-digital workflow, you should not forgo
this important step. Besides printing a hard copy,
consider soft proofing onscreen as an extra check.
Soft Proof: Using profiles allows you to soft proof
printing intent on your monitor … provided, of
course, that you have quality profiles for your monitor
and your print condition. The output profile
conveys a lot of information about print conditions
such as the tone and color response of the print
device, along with how inks interact with a specified
stock. Choose Custom Proof Setup from the View
menu in any Adobe application. Choose the custom
printer/proofer profile in the Device to Simulate
menu. You may also choose a standard printing
profile that best reflects the print job (U.S. Sheetfed
Coated v2, etc.). Check Black Point Compensation
and choose either Perceptual or Relative Colorimetric
for Intent. Check Simulate Black Ink and
Paper Color to preview shadow details and the
overall effect of printing on the chosen stock.
Once you click OK, you are effectively soft
proofing the profile, as indicated by the profile name
in the title bar. This view can be toggled on and off
by typing Command/Control+Y. While soft proofing,
you can add adjustment layers for various outputs.
Printed Proof: If you have a profiled printer in your
studio, print a color-managed proof now. (In the
next article in this series, I’ll show how to match
output from your desktop printer to your monitor.)
If you don’t have a profiled printer, have your
print provider proof your RGB artwork. Ideally,
send the printer your master RGB file saved with the
working space profile. The printer will convert the
file to the final output space using a custom profile or
printing standard such as U.S. Web Coated (SWOP).
9. Save with profile.
Save the master RGB file with layers in an uncompressed
file format suitable for archiving. Some good
choices are the native file formats for Photoshop,
Illustrator, or InDesign. Another option is a universal
uncompressed format such as TIFF. Be sure to
embed the working space profile in the document.
To convert a file for any form of output, duplicate
the image, then convert the copy to the final
output space by choosing Edit > Convert to Profile
and choosing the output profile as the Destination
Space profile. Save the converted art in a format that
supports embedded profiles (EPS, PDF, or JPEG).
Once you implement this RGB-based workflow,
you’ll find that your color work is streamlined and
appears consistent across multiple outputs. You’ll
be more productive and prepared to offer a faster
response to your clients’ varied output needs.
Web resources
Amladi offers valuable tips on synchronizing color settings in Adobe applications, quick color correction, finding clues about an image's embedded profile, and effective file management in our additional online coverage.
Coming up: In the next issue, I’ll show you how to:
- Ensure that your
studio printer’s color
output matches your
monitor.
- Get your profiled
studio printer to accurately
preview press
results.