Epson GT-6500 EN - Manual (Page 35)

Image processing
Halftoning
For documents with many shade gradations (like a photograph) in
full-color mode (24-bit data), you can faithfully reproduce the image
on a full-color output device. Some output devices, such as 8-color PC
monitors or 8-color printers, cannot faithfully portray a full-color
image; however, a method does exist for approximating multiple
shades on these types of output devices.
For example, by adjusting black and white pixels slightly,
you can approximate various shades of gray between black
and white. This type of data processing is called halftone processing,
and several versions are available on EPSON scanners. Two typical
forms of halftone processing are dither processing and density pattern
processing. Dither processing is the normal type of data processing
found on scanners. EPSON scanners also represent halftones using
dither processing.
Halftone mode A Halftone mode B
Overview 1-21