46VISIONEER ONETOUCH 8920 SCANNER INSTALLATION GUIDE
For example, if you select Red from the menu and drag the Brightness and Contrast sliders, you can see how the red component of the histogram changes. Note, however, that the Green and Blue components also change relative to those new brightness and contrast settings.
3.Click the Auto button to have the scanner analyze the image and set the appropriate brightness and contrast.
You can also adjust the brightness and contrast by sampling portions of the image in the preview window. The three Sampler buttons correspond to the Black, Mid tones, and White portions of an image.
To use the Sampler buttons:
1. Click one of the buttons.
The pointer automatically moves onto the image and becomes a sampler pointer.
2.Place the pointer on the portion of the image for that sample and click.
For example, if you selected the Black sampler button, place the pointer on the blackest part of the image.
3.Repeat with each of the other Sampler buttons.
4.Click Adjust.
The image changes to show your new settings.
If the image is not what you want, click Reset to return the image to its original brightness and contrast.
ADJUSTING GAMMA, SATURATION, AND COLOR HUE
If you’re using the Color Configuration to scan, you can adjust a group of color settings. Gamma controls the brightness of the midtones of the color, saturation is the strength or purity of a color, and hue is the color your eyes see as reflected from the image. These color settings are represented by a response curve.
