Step 3: Set The Highlight And Shadow Values - Adobe PHOTOSHOP 5.0 User Manual

114 CHAPTER 6
Making Color and Tonal Adjustments
Step 3: Set the highlight and
shadow values
You begin professional tonal correction by
assigning values to the extreme highlight and
shadow pixels in the image, setting an overall
tonal range that allows for the sharpest detail
possible throughout the image. This process is
known as setting the highlights and shadows or
setting the white and black points. You can do
this several ways.
Determining highlight and shadow values
High-key and low-key images may benefit from
slightly different target values than those suggested
in "Setting the highlights and shadows using target
values" on page 114:
With a low-key image, you might want to set the
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highlight to a lower value to avoid too much
contrast.
With a high-key image, you might want to set
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the shadow to a higher value to maintain detail in
the highlights.
Experiment with shadow Brightness values
between 4 and 20 and highlight Brightness values
between 96 and 80.
Use an adjustment layer for each color
correction technique described in this
section. Adjustment layers let you experiment
with different color correction settings without
permanently changing underlying pixel values.
(See "Using adjustment layers" on page 281.)
For a color illustration on determining
highlight and shadow values, see page 230.
Setting the highlights and shadows using
target values
Professional color technicians typically set the
highlights and shadows in the image by assigning
their lightest and darkest CMYK ink values to the
lightest and darkest areas of detail in the image.
It's important to identify a truly representative
highlight and shadow area. Otherwise the tonal
range may be expanded unnecessarily to include
extreme pixel values that don't give the image
detail. A highlight area must be a printable
highlight, not specular white. Specular white has
no detail, and so no ink is printed on the paper. For
example, a spot of glare is specular white, not a
printable highlight.
Selecting the specular highlight area and the representative
highlight area
To set the highlight and shadow using target values:
Select and double-click the eyedropper tool ( )
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to display its Options palette.
For Sample Size, choose 3 by 3 Average.
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