User`s guide

DocuMate 765 Scanner User’s Guide 63
Scanning from TWAIN
Color Dropout tells the scanner and software to remove a specific color
from the image. You can choose either Red, Blue or Green to be dropped
out of an image. This option is only available when scanning in grayscale
or black and white.
Brightness is the overall lightness of the image. Move the slider to the
left to decrease (darken) the image, move the slide to the right to increase
(lighten) the image. You might use this option if you are scanning in a
document with handwritten notes using a pencil. This option is only
available when scanning in Color and Grayscale.
Contrast refers to the difference between the light and dark portions of
the image. Increasing the contrast emphasizes the difference between
the lighter and darker portions, decreasing the contrast
de-emphasizes that difference. This option is only available when
scanning in Color and Grayscale.
Threshold technique is specific to the type of documents you are
scanning. When you select a threshold technique the sub-panel below will
update with the options available to that technique. These options are
only available when scanning in Black and White.
• Text (threshold) enables you to set what level of light or dark text to
look for on a page. When scanning in black and white, everything on
the page is set to either white pixels or black pixels in the final image.
If the text on the page is a light color, then the text may be gone in the
final image as the scanner will change those light colors to white
pixels. The text threshold technique lets you set the level of darkness
or lightness of the text on the page. This option works best for
document that contain only text such as business letters,
spreadsheets, reports, etc...
• Photo (dither / halftone / error diffusion) is the intentional
application of noise in the image to help alleviate banding when
scanning in binary (Black and White) mode. For example, if you scan
a color photo in black and white, the image file will have large blocks
of black and white and the image barely recognizable. Dithering the
image creates a black and white image that is recognizable. The
dither option is only available when you are scanning in Black and
White.
• Mixed content (automatic separation) applies both a threshold
level and a dither diffusion to the image. It looks at the page and
breaks it up into sections of graphics and text, then applies the
threshold and dither value the appropriate section. This option works
well when scanning items that have both text and graphics, such as
marketing brochures. After selecting this technique, both sub-options
for Threshold and Dither will be available.
• Dynamic threshold enables you to set what level of light or dark text
to look for on a page. When scanning in black and white, everything
on the page is set to either white pixels or black pixels in the final
image. If the text on the page is of a light color, then the text may be
gone in the final image as the scanner will change those light colors
to white pixels. The text threshold technique lets you set the level of
darkness or lightness of the text on the page.