Building Camera Profiles - Color Management for Photographers - page 169

what RAW converter will be used and whether the converter can utilize
ICC profiles to define the processed RGB data.
Creating an ICC profile for a digital camera is a simple process, at least
in theory. We start by having some standard target with known color
values. We photograph the target, using the correct exposure and proper
lighting, and bring this target into some third-party software that can
build an ICC profile. The software examines and compares the provided
RGB data with the known values of the target. With those two pieces of
information, the software can produce an ICC profile. This is fundamen-
tally the same process discussed for building a scanner profile. Let's look
at the various components just discussed in more detail, and then
examine how this process operates in the real world.
Targets
Like the various scanner targets discussed in Chapter 4, there are also a
number of targets used to build digital camera profiles. The original and
most common target is the GretagMacbeth ColorChecker seen in Fig. 5-6.
This 24-patch target was never designed for creation of camera profiles,
but rather to be included in some images as a useful color reference. The
vast majority of products that build camera profiles will accept this target.
The ColorChecker can work reasonably well, but has some limitations.
With only 24 color patches, all matte in surface texture, the resulting
color gamut of a profile can be much lower than using other targets. The
gamut of the target defines the gamut of the resulting profile. Digital
Fig. 5-6 The
GretagMacbeth target
known as the
ColorChecker .