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

Color Table Not applicable for bi-tonal images. See the next section “Scanning color images”.

A-61512 May 2006

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Kodak i30 / i40 manual Dpi 80 Threshold 200 dpi Contrast 100