Woody Pond, Georgia
You finally jumped into the wonderful world of digital print making. You
bought the equipment, set it all up, and your prints look terrible because
the colors are not right. You make color adjustments and waste tons of
expensive paper and ink, only to come up with a mediocre result. Now you’re
ready to throw all your equipment out the window. Nearly everyone who
strives for high quality prints has gone through this frustration. Although
this article is not an exhaustive technical study of color management it
should get those who are new to the subject of color management started in
the right direction and demystify the topic. Perhaps it will save you some
of the frustration I went through many years ago.
Understanding the Problem
Every physical device deals with color in its own unique way. Film scanners
may use either a LED (Light Emitting Diode) or fluorescent light source for
capturing the film image on a CCD (Charge Coupled Device). Some digital
cameras use CCD based technology too, but several very different designs are
used by the various manufacturers. Each monitor manufacturer uses its own
electronic circuit design. Inkjet printers made by various manufacturers use
different technologies to spew ink formulated by various other manufactures
onto paper made by still other manufacturers to produce color prints.
Without any set standard, it is obvious that any given color will not look
the same on all of these devices. Fortunately, there is a solution known as
color management, where calibration or profiling of each device to a known
standard gives consistent and accurate results.
A color space simply defines a range of possible colors. Colors possible in
one color space may not be possible in another, and all are more limited
than the range of colors that exist in the real world. Your digital camera,
film scanner, monitor, and printer all operate within their own unique and
non-standard color spaces. Some devices never expose their unique color
space to the outside world, and instead translate it into one of several
standard color spaces internally, before you ever see the data. The first
step in managing color on an imaging system is to decide on a system-wide
“standard” color space within which all images will be viewed and adjusted.
This is often called the "working color space". There are a number of
standard color spaces that are used for various reasons. The most common
standard color spaces for photographic imaging are sRGB and Adobe 1998. The
sRGB color space is the standard for Internet use because it most closely
represents the way un-calibrated color monitors reproduce color. sRGB is
frequently used for color printing too, but it is one of the more limited
spaces. Adobe 1998 is a larger color space that enables a wider range of
tonalities and is therefore better for critical printed work. It is
important to remember that images meant for one color space will look
terrible when viewed in a different one. For instance, if you put your Adobe
1998 images on a web page without converting them to sRGB, they will look
dull and muted. Pro Photo is a color space that is so large it contains
colors that the human eye cannot see.
Device Color Profiles
Any color can be represented within its color space by a set of three
numbers that define its red, blue, and green components. It is the job of
device color profiles to translate or map each color in the device’s color
space to a color in the “standard” color space. Once a color is translated
into a standard color space it will look the same on every device that has
an accurate mapping (color profile) between its own color space and the
standard one. These profiles are the key to getting accurate color from your
system. Device color profiles can be created, bought, or supplied free by
equipment manufacturers. For a totally color managed system, digital
cameras, scanners, monitors, and each printer, paper, and ink combination
need a profile. Since you look at a monitor to decide on color adjustments,
and you then want those adjustments accurately reflected in your prints, the
most important profiles are for your monitor and printer.
The most accurate way to profile your monitor is to purchase a commercially
available monitor calibration package. These use software together with a
hardware device to measure the colors produced by your monitor and
automatically produce a very accurate color profile for it. These are
available from several manufacturers. Just follow the provided instructions.
These calibration solutions are worth every penny they cost, and you won't
be sorry you bought one.
There are a few different approaches you can follow to get accurate color
from a printer. They are:
1. Buy a hardware and software package that
creates a profile for any printer, paper, and ink combination you choose.
These cost between a few hundred to thousands of dollars. It may be worth
getting one of these if you experiment with many different paper and ink
combinations, each of which requires a profile, or if your printer
manufacturer has no color profiles available for your printer model.
2. Buy a profile for your printer, paper, and ink combination from a third
party supplier. You can easily find suppliers on the Internet. These are not
particularly cheap, but if you only need a few this can be a cost effective
way to obtain custom printer/paper profiles.
3. If your printer
manufacturer supplies profiles for their own brand of printer, ink, and
paper, you can simply use these and stick with the paper and ink recommended
by the manufacturer. Some Epson printers are supplied with excellent color
profiles that are hard to beat under any circumstance.
4. Many paper
manufacturers supply free profiles for using their paper on various popular
printers. The quality of these can vary widely, but in recent years profiles
from the better known paper manufacturers are excellent.
controls in the printer driver to adjust the printer to print what you see
on the calibrated monitor. From then on, use those settings when you print
using the same paper and ink. This method is the least accurate and it is
more easily described than done.
Manufacturer’s Generic Profiles and Other Devices
Many digital cameras and scanners are calibrated for sRGB or have selectable
color space profiles that include sRGB and Adobe 1998. These settings invoke
generic manufacturer supplied profiles that translate the camera’s color
characteristics to the appropriate color space. Sometimes individual
cameras, scanners, and printers can vary significantly from the average for
a given model. Manufacturer supplied generic profiles for all of these
devices may or may not be adequate. It all depends on how close your
individual device is to “normal” and how critical you are. If your monitor
and printer are accurately calibrated you will always see what you’ll get
before printing, so minor inaccuracies in camera and scanner profiles may be
acceptable. More accurate results from digital cameras can be obtained by
using profile aware RAW file conversion programs like Capture One and Adobe
Only the Basics
This article has presented only the most basic concepts of color management.
Although a lot more can be learned about this topic, a good implementation
of these basic concepts is enough to begin making excellent prints.
Obtaining accurate equipment profiles and using them properly will save
plenty of ink, paper, and frustration.
Please note that this is an
essay is nearly ten years old. In November of 2013 it was purged of information
that had become useless or irrelevant. What remains are concepts that have
not changed. It can therefore still be of use to those wanting to better
understand the principals of color management.