Operation Manual

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Defi ning “Shadows” and “Highlights”
The Threshold slider in the detailed view of the “Digital
DEE” panel determines the border between shadows and
highlights.
Moving the slider to the right or entering a higher value in
the Threshold text box increases the range of tones affected
by the Shadow Adjustment slider and reduces the range of
tones affected by the Highlight Adjustment slider.
Try increasing the threshold value if shadow brightness fails
to brighten shadows in the desired tone range, or if highlight
adjustment is affecting too great an area.
Moving the slider is to the left or entering a lower value in the
Threshold text box increases the range of tones affected by
the Highlight Adjustment slider and reduces the range of
tones affected by the Shadow Adjustment slider.
Try decreasing the threshold value if highlight adjustment
fails to increase contrast in the desired tone range, or if
shadow brightness is affecting too great an area.
Threshold
slider and
text box
Shadows
Threshold
Highlights
Tone range affected by
Shadow Adjustment
Tone range affected by
Highlight Adjustment
Shadows
Threshold
Highlights
Tone range affected by
Shadow Adjustment
Tone range affected by
Highlight Adjustment
Threshold
Threshold
Ideally, the threshold for shadow adjustment should be twenty to forty
greater than the highest of the R and G values in the brightest shadows.
The threshold for highlight adjustment should be twenty to forty less
than lowest of the R and G values in the dark-
est highlights. To choose a threshold that can
be used for both shadows and highlights, enter
the average of the highest value (R or G) in the
brightest shadows and the lowest value (R or G) in
the darkest highlights. Color values can be deter-
mined by moving the cursor over the image and
observing the R and G values in the scan window
information panel.
The Tool Chest — Digital ICE
4
Advanced