Ricoh IS450 Photo Scanner User Manual


 
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Halftone Scanning
Halftone scanning converts the original into an image consisting of pseudo-halftones produced
by dot shading (in which shading is achieved through combinations of black and white dots, as
in newspaper photographs). This function is used to output an original that has intermediate
tones, such as a photo, on an output device that can only produce monochrome output, such as a
laser printer.
Because halftone scanning expresses pseudo-halftones, it does not require as much memory,
making it effective for filing a large volume of images. There are eleven types of halftones (ten
dot shading patterns and one error diffusion pattern) for selection. It is also possible to scan and
download your own dot shading patterns.
The names in parentheses indicate the names under the ISIS driver.
Original
8 x 4 45° 6 x 6 90° 8 x 8 90° 16 x 8 45°
Error diffuson8 x 8 Bayer4 x 4 Spiral16 x 16 90°
Functions