Used to correct the brightness and contrast of an image.
[Brightness] group
The current setting appears in the middle. Brighter images appear above, while darker images appear below.
[Contrast] group
The current setting appears in the middle. Images with less contrast appear on the left while images with more contrast appear on the right.
[Level] slider
The amount of brightness and contrast correction can be adjusted. As you move the slider to the right, the amount of correction increases.