Kodak i55 User Manual page 43

Threshold  used to convert a grayscale image to a bi-tonal image.
The thresholding value is an integer ranging from 0 to 255. A low
threshold value produces a lighter image, and can be used to subdue
backgrounds and subtle, unneeded information. A high threshold value
produces a darker image, and can be used to help pick up faint images.
Adjust the threshold setting by dragging the Threshold sliding bar to the
left or right to achieve the desired threshold setting, or you can enter a
value (0 to 255) in the Threshold text box. Scan the document to check
the threshold.
200 dpi; 80 Threshold 200 dpi; 80 Threshold
20 Contrast 100 Contrast
Resolution or dots per inch (dpi)  indicates the scanning resolution,
which largely determines the quality of the scanned image. The greater
the resolution, the better the reproduction. However, scanning at a
higher resolution also increases scanning time and file size. The
industry standard is 200 dpi (about 8 pixels/mm).
Choose a resolution value from the drop down list. The default value is
200 dpi. Available resolutions are 75, 100, 150, 200, 240, 300, 400 or
600.
Polarity  the host PC provides information to the scanner defining
whether the image should be stored in standard or reverse polarity. The
default polarity is Black on a White background. Reverse polarity is
White on a Black background.
Black on White polarity White on Black polarity
A-61527 May 2006
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