6.2.7.3 The Hue-Saturation Tool
The Hue-Saturation dialog is shown in
Figure
6.27.
Figure 6.27:
The Hue-Saturation Tool
 |
This tool is more complex than either the
Color Balance or
Brightness-Contrast tools, and its action cannot be simply reproduced
using
Curves. Nevertheless, there is rarely any reason to use
this tool for touchup or enhancement. The
Hue-Saturation tool
allows hue, lightness, and saturation to be adjusted for an image.
The adjustment can be made for the entire image or for any combination
of the image's red, green, blue, cyan, magenta, or yellow components.
The reason Hue-Saturation is not useful for color correction is
that it is difficult to know how to make adjustments with it to
enhance an image. With the Curves tool, the measurements made
with the Color Picker can be used to make precise changes that
will result in predictable improvements to an image. By contrast,
there is no way to measure what is wrong in an image in a way that can
then be used to make precise corrections with the Hue-Saturation
tool. Furthermore, as has already been pointed out, color problems
are rarely uniform over the shadow, midtone, and highlight regions.
The Hue-Saturation tool has no capability for varying color
components in different ranges of the image.
Thus, for color correction, the Hue-Saturation tool is of little
use. Nevertheless, unlike Color Balance and Brightness-Contrast, the Hue-Saturation tool can be used to do
useful and interesting things that would be difficult to do with any
other color tool. Figure
6.28
Figure 6.28:
Hue-Saturation
 |
illustrates an application of the
Hue-Saturation tool which
doesn't fit into the category of touchup or enhancement but is of
considerable stylistic and artistic interest.
Figure
6.28(a) displays a beach scene
consisting of vivid colors, and
Figure
6.28(b) shows the Hue-Saturation dialog where the Saturation slider for the Cyan radio
button has been adjusted to -100%. The result, shown in
Figure
6.28(c), is to completely desaturate
the sky and water, while leaving the color of the beach untouched.
Similarly interesting modifications can be made with the Hue and
Lightness sliders. Try experimenting!
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