Avision AV810C+ - Manual (Page 36)

4-11
G ray (4096 levels gray scale/Internally)
A single-channel image consists of at least 256 levels of shades of
gray in an image. A 12 bits scanner produces a Gray
image with
4096 shades of gray between pure black and pure white. Gray is
the best choice of image if you wish to scan a black and white
photograph. With 12 bits of color information per pixel, the disk
space required to save a gray image is eight times more than
lineArt and 1/3 of that required to save a 24-bit true color image.
Figure 4-7 A Gray Image