Canon MP-C635, Руководство пользователя

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Chapter 6 Scanning With the MultiPASS C5500 6-23
Scanning
Here is the same adjustment using the Perform in Hardware check box.
Because the adjustment was made inside the MultiPASS, the quality of
the image will be smoother, with less posterization.
Adjusting Color Distribution Values
You may have heard of a device called the Densitometer. This device is
used in the printing industry to measure the amount of ink on the
printed page. It is usually found in the company of Cyan, Magenta,
Yellow, and Black print jobs.
The software industry has borrowed this term for describing the color
values of an individual pixel of image data. This is very useful in
programs such as Photoshop where a conversion has been made
between the light we see (Red, Green & Blue) and the separations used
to produce printed material with Cyan, Magenta, Yellow and Black inks.
The information it provides helps the user decide if the separation will
print properly with the correct tonal cast, etc.
Since ScanTastic only deals with RGB data (as is the case with all
scanners since they capture the light reflecting off an image), this
information is referred to as an Intensitometer (Intensity of light)
instead of a Densitometer (Density of ink).
The Intensitometer section gives exact values for the pixel directly under
the pointer identifying the distribution of color it contains. This
information is best used to determine if there is contamination in gray
shades. The number on the left is the original value. The number on the
right indicates the corrections you have made with enhancements.