Both Uses

contrast
in
The Witch of Blackbird Pond
(Edited)

The bleak line of shore surrounding the gray harbor was a disheartening contrast to the shimmering green and white that fringed the turquoise bay of Barbados which was her home.
p. 2.1 *

contrast = something notably different compared (to something else)
The two girls who set out soon after breakfast did not provide such a contrast as on Meeting Day.
p. 75.2

contrast = something notably different

Definitions:

(1) (contrast as in: contrast their writing styles)
point to differences between; or compare to show differences
(2) (contrast as in: there is a contrast)
a difference -- especially a notable difference; or the side-x-side arrangement of things that draws attention to an unmissable difference
(3) (contrast as in: sharpen the picture contrast)
the difference between tones of an image -- as in a photo or video -- such as the quality of brightness or the intensity of shades or colors
(4) (meaning too rare to warrant focus)