CHAPTER 2: Understanding Key Color Management Concepts
18
Rendering intents determine how the
color of one device converts to another
device. Depending on the color and
tonality in the two di erent color spaces,
the di erences can range from minimal to
fairly dramatic. When converting from one
space, such as RGB, to another, such as
CMYK, we go though the PCS (discussed
in “PCS Source and Destination, earlier
in this chapter). There are four di erent
rendering intents that ICC pro les may
have for resolving color di erences:
perceptual, saturation, relative
colorimetric, and absolute colorimetric.
The images here illustrate the di erences
among the four di erent rendering
intents. The e ects of the di erent
intents have been exaggerated so
that they are easier to distinguish
visually. Even with the exaggerated
colors, it is still sometimes di cult
to see the subtle di erences.
Original image
Rendering
Intents
As you’ve learned, di erent devices have di erent size
gamuts. When you convert from one color space to another,
the colors and tones need to be changed to t into the new
color space. The rendering intent is the strategy for resolving
the di erences in color space.
ETCM_book.indb 18 10/6/06 4:31:56 PM
Perceptual
This intent (sometimes referred to
as photographic) tries to preserve
the overall color appearance by
changing the colors of the source
image to  t into the destination space.
It sacri ces accuracy to produce
a more visually pleasing image.
This intent is very useful when the
source has a wide gamut and the
destination has a small gamut.
Saturation
This intent tries to produce the most
vibrant color by pushing the color of
the source image out as far into the
destination space as possible. It is not
used much by photographers but is
often used for business graphics to
achieve bold color in presentations.
Relative colorimetric
This intent is used when color
accuracy is the most important
concern and is the default rendering
intent in the more recent versions of
Photoshop. It works very well when
the source and destination pro les
have similar gamuts. If the gamuts
of two devices are too di erent from
one another, the more saturated
color may be clipped or minimized.
Absolute colorimetric
This intent is usually used for proo ng
when trying to simulate one device
on another. It is similar to relative
colorimetric, except all the color
adjustments are based on the white
point. Unlike relative colorimetric,
absolute colorimetric shows the white
of the source pro le. In some cases,
this intent can create an undesirable
color cast if used as a default.
Relative colorimetric
Saturation
Perceptual
Absolute colorimetric
Rendering Intents
19
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