Microtek ScanMaker 6100 Pro User Manual page 80

Sliders
The sliders are used to adjust the Black and White points of the
image. The values of the black and white points are reflected in the
edit boxes below.
Auto
The Auto button automatically judges the darkest and whitest
points and clips excessive black or white points. The clipping
percentage of the white/black points is accessible by clicking the
Setup button.
Channel
The channel button lets you control the shadow and highlight
settings for a particular color channel (red, green, or blue), or for
the All/Master channel (red, green, and blue simultaneously). For
CMYK images, the channel selections are cyan, magenta, yellow and
black (for K).
Input, Count, Percent
These figures provide information about the histogram. The figures
will appear only when the cursor is on the histogram or if a slider is
being moved.
The Input value indicates the color value of the data displayed
in the histogram.
The Count value indicates the number of pixels at the Input
value. If Input value is 2 and Count value is 1300, then there
are 1300 pixels in the image at the Input value of 2.
The Percent value is the percentage of all pixels in the image
where color value is less than or equal to the input value. For
example, if Percent is 15% and Input value is 2, it means that
15% of all pixels in the image have a value of 2 or less.