The scale function affects the number of dots scanned. An image scanned at 180 dpi and 200% has the same number of dots as an image scanned at 360 dpi and 100%.

To enlarge or reduce the image size, use the scanner’s scale function through your software at the time of scanning. Avoid increasing the image size after scanning because the image quality deteriorates. The default scale value is 100%.

Data Format

The data format specifies the number of bits used to represent the tone of a pixel. The data format can be set in the range of 1 bit to 8 bits per pixel per color.

As the value increases, more tones and colors can be captured in the scanned image. In monochrome, 1 bit/pixel (bi-level data) can represent only two levels of tones, black (0) or white (1). With 2 bits/pixel (quad-level data), four levels of tones can be represented by the binary values of 00, 01, 10 and 11. Using

8 bits/pixel corresponds to 256 shades of gray, producing near photographic quality results.

In color, the data format defines tones for each of the three primary colors of green, red, and blue. One bit/pixel/color can represent eight colors (2 × 2 × 2), and 2 bits/pixel/color can represent 64 colors (4 × 4 × 4). Eight bits/pixel/color (total 24 bits for a pixel) can represent over 16 million colors.

Expression 636 Scanner Settings B-3