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Hack 52 Great Color Prints from Your Inkjet Printer

The battle cry for his hack is
"go forth and calibrate!"
That's about the only way you're
going to get consistently accurate prints from your inkjet
printer.

One of the promises of digital printing is that you
can produce images in your own digital darkroom without the mess of
mixing chemicals. However, while there is no water involved in
digital printing, your prints might still get wet from the sweat of
frustration.

If you've ever tried to print color photos by just
plugging your camera into the computer, opening your image, and
printing, you know where this frustration comes from. Consistent
color out of the box is almost impossible without a little upfront
work. But, if you follow the techniques outlined in this hack, what
you see on your monitor will look very much like what you print out.

The solution starts with your monitor. Monitors are made by a wide
variety of manufacturers. This results in a surprising array of color
variance between your monitor and another brand. Even the age of a
monitor affects its color. This means that the perfectly
color-correct image on your monitor might not really be
color-correct. The only real way to ensure that the color on your
monitor is consistent with the color on your printer is for them to
work off the same protocol. The industry-standard software for this
protocol is documented by the International Color Consortium (ICC), a
group founded by Apple and seven other vendors in 1993. The most
popular and mature implementation of the ICC system is
Apple's own
ColorSync
(http://www.apple.com/macosx/features/colorsync/).
Using ColorSync, you can match what you see on your screen to what
you see on paper with uncanny accuracy.

ColorSync is built into the Macintosh operating system (including Mac
OS X, 9, and older versions) in a seamless way. If you have a PC,
don't fret. While the ICC system is not as well
integrated into Windows as it is on the Mac, it's
still possible to utilize a color-management workflow.

5.7.1 Measure Me

For this hack, you need to purchase a
colorimeter,
which measures color densities and enables you to calibrate your
monitor. There is really no way around using a colorimeter if you
want truly accurate color on your monitor. Popular brands start at
US$150 and include the Pantone Spyder,
Monaco Sensor,
and the Gretag Eye-One Photo. You can find many
models at Amazon.com (http://www.amazon.com). Some colorimeters can
calibrate only CRT monitors, so if you have an LCD monitor, make sure
to purchase a colorimeter than works for you.

You could use the Adobe Gamma tool that comes with Adobe Photoshop,
but because this is entirely a software tool, your results will be
mixed at best. A colorimeter is a little camera that you place on top
of your monitor and plug into your computer. You then run an
application that comes with the colorimeter. Depending on the
software included, your monitor will go through a series of routines,
flashing different screens of color and making what might seem like
strange patterns. The colorimeter reads these colors and, using
software, creates an ICC profile for your monitor. By having your
monitor calibrated to an ICC profile, you've taken
an important step toward output that looks like what you view on the
screen.

The implications of calibrating your monitor are fantastic. Now, when
an image has too much yellow in it, you know that it really has too
much yellow in it. Calibration will not automatically fix your
images, but it will give you the ultimate control to see what needs
to be fixed. And when you begin using levels or curves to makes
adjustments, you will be doing so with the utmost accuracy. Yes, a
more expensive monitor will give you even more accuracy, but even a
relatively cheap monitor that is calibrated using a colorimeter
provides a quantum leap in accuracy.

5.7.2 Print Me

With your monitor calibrated accurately, the next step is to get
whatever you print to match, as closely as possible, what you see on
your screen. You could go out and buy a colorimeter that will
accurately match your printed output, as described in the previous
section. However, because printers have much tighter tolerances than
monitors, this isn't necessary. (But if you have
money to burn, or if you want to take your color accuracy to the next
level, go for it.)

Printer manufacturers include ICC profiles with their printers, as shown
in Figure 5-9. Many manufacturers even include
different profiles for different papers. For example, my Epson
printer comes with profiles for matte paper, glossy paper, and a
number of different varieties in between. This is because, depending
on the actual paper's substrate on the color gamut
(or amount of colors), your print output can vary from
paper surface to paper surface.

Figure 5-9. Available ICC profiles for a few Epson printers

When working with images in Photoshop, make sure to work within the
RGB (red, green, and
blue) color space, and don't convert your images
yourself to CMYK (cyan,
magenta, yellow, and black). Yes, most inkjet printers use CMYK to
print (some use additional tints to achieve even more colors), but
believe it or not, the software that runs these printers works in the
RGB color space. Also, when you convert your image to CMYK, you are
not converting it to a generic version of CMYK; you are converting it
to a specific color space (the default version in Photoshop is US Web
Coated, Webin this case, meaning web offset printing).

Using profiles and the soft-proofing feature built into Photoshop,
you can simulate how your image will look when printed, without ever
having to actually change the color space of the image. You can
access these profiles right within Photoshop to preview how your
photo will print. Go to ViewProof SetupCustom and
select your printer/paper combination from the drop-down menu, as
shown in Figure 5-10. Click OK. The colors in your
image will change either subtly or dramatically, depending on your
image and the profile used.

Figure 5-10. Previewing how your image will print in Photoshop

Because your monitor is accurately calibrated, you can be certain
that the yellowish cast in your image will appear yellowish when you
print. Now, you can accurately adjust the yellow cast on your monitor
before printing. When you do print, make sure you select
"No color correction" from the
Epson printer setup window. If you don't select that
option, Epson's own color-management feature will
kick in, ostensibly color-managing your already color-managed
image.

5.7.3 Lighting

Walk into any
gallery or museum and
you'll immediately notice the quality of the light.
These institutions spend plenty of money and time to make sure their
color cast is as neutral as possible. That way, a Monet in Paris will
look the same in New York. You need to do the same thing with your
photos; otherwise, all the work you have done to get good color will
be lost when you look at them under that tungsten light bulb.

You can neutralize your color cast either by purchasing a viewing
booth with neutral lighting or by putting together your own
rudimentary, but pretty accurate, viewing environment. A neutralized
workspace is achieved by combining tungsten lighting with fluorescent
lighting. Local art stores sell desk lamps that incorporate both
tungsten and fluorescent bulbs, but you can also make your own
viewing area by having two lights: one fluorescent and the other
tungsten of equal wattage. Make sure to view your prints in this
light and make any color decisions here.

Now that your monitor, printer, and desk space are color-calibrated,
you can now make adjustments in Photoshop confidently.

Hadley Stern