Avision AVA3 400 - Manual (Page 42)

Scanner Operation
4-15
Highlight/Shadow:
Highlight refers the lightest point in a scanned image
while shadow refers the darkest point. Using
Highlight and Shadow tool together allow you to
extend the range of color and reveal more details in
a gray or color image.
Highlight: 255/Shadow: 0(Normal) Highlight: 210/Shadow:10
Highlight: 200/Shadow:0 Highlight: 255/Shadow: 50