User Manual

Histogram Controls
These controls along the bottom of the histogram display are used to adjust the input image’s
histogram, compressing or shifting the ranges of the selected color channel.
The controls can be adjusted by dragging the triangles beneath the histogram display to the left
and right.
Shifting the High value toward the left (decreasing the value) causes the histogram to slant
toward white, shifting the image distribution toward white. The Low value has a similar effect in
the opposite direction, pushing the image distribution toward black.
Output Level
The Output Level control can apply clipping to the image, compressing the histogram.
Decreasing the High control reduces the value of pixels in the image, sliding white pixels down
toward gray and gray pixels toward black.
Adjusting the Low control toward High does the opposite, sliding the darkest pixels
toward white.
If the low value were set to 0.1, pixels with a value of 0.0 would be set to 0.1 instead, and other
values would increase to accommodate the change. The best way to visualize the effect is to
observe the change to the output histogram displayed above.
Reset All Levels
Clicking this button resets all the controls in the Levels section to their defaults.
Correction Tab Histogram Menu
When the menu is set to Histogram, a histogram display is produced of the input image. If a
reference image is also provided, the histogram for the reference image is also displayed. The
controls in this tab are primarily used to match one image to another, using either the Equalize
or Match modes of the Color Corrector.
Chapter – 85 Color Nodes 1861