Canon MultiPASS F20 Software User's Manual page 78

2. If you are working with a color image, click the appropriate color
channel.
3. Move the slider to the left to decrease, to the right to increase, the
contrast displayed in the middle of the tonal range (midtones) of your
image. Or, enter the value in the box.
4. To return to the original setting, click Reset.
To adjust the tone using a histogram:
1. On the Tone tab, click Histogram.
Chapter 4 Scanning 74