User Guide

Chapter 2
38 VRS User’s Manual
Automatic Image Enhancement
As stated previously, VRS has the ability to monitor images, detect poor image
quality, and perform automatic image enhancements that greatly reduce image
quality and recognition errors. For more information about manual image
adjustment, refer to “Manual Image Adjustment” on page 46.
Brightness and Contrast
When the Auto Brightness check box is selected, VRS automatically assigns optimal
values for brightness and displays those values in the manual Brightness slider and
numeric text box. The Auto Brightness feature is not available when you scan images
in color. It becomes available only when scanning in grayscale and black and white.
Note Moving the Brightness slider, entering a value in the Brightness numeric text
box, or clicking in the Brightness-Contrast custom control turns off Auto Brightness.
Figure 2-30. Auto Brightness Check Box
Gamma and Gamma Correct
When a scanner scans your document, it determines how to convert the light intensity
of that document into pixels using a value called gamma. When scanners have an
incorrect gamma value or no gamma encoding, image quality can be adversely
affected. In most cases, VRS default settings will prevent this problem. The Gamma
slider and the Gamma Correct box are available for extreme cases in which
documents require manual gamma adjustments. Otherwise, you should keep the
gamma default value.