User Guide

Chapter 5: Editing
137
Shadows Specifies the black point of an image.
Move the slider, or type a number from 0 to 255 into the spin box, to define
the color value which will become zero (black). All color values in the image
below this level will be clipped to zero, the image will become darker and
contrast increased.
Midtones Specifies the midpoint of an image. A gamma curve is applied, causing
contrast and brightness in the areas below and above the new midpoint to
be increased/decreased relative to one another.
Move the slider, or type a number from 0.00 to 2.00 into the spin box, to
set the amount of gamma correction. Higher values make the image appear
brighter, while lower values make the image appear darker.
Highlights Specifies the white point of an image.
Move the slider, or type a number from 0 to 255 into the spin box, to define
the pixel value which will become 255 (fully saturated/white). All pixel
values in the image above this level will be clipped to 255, and the image
will become brighter and contrast increased.
Clipped % Indicates, or specifies, how much of the image detail is lost due to black-
point and white-point correction. If you adjust this percentage, the
corresponding black or white point changes accordingly.
Black Point
picker
Click the Black Point picker, and then click the image area you want to set
as the black point.
Mid Point
picker
Click the Mid Point picker, and then click the image area you want to set as
the mid point.
White Point
Picker
Click the White Point picker, and then click the image area you want to set
as the white point.
Auto Select one of the following options:
x Adjust Contrast: Automatically sets the black and white points in the
Luminance channel.
x Adjust Color and Contrast: Automatically analyses and sets the
black and white points individually in each color channel.
x Adjust Color and Brightness: Automatically analyses and sets the
color and brightness of the image.
x Tolerance: Opens the Tolerance settings dialog box where you can
specify the percentage of pixels in the image which should be clipped
by the automatically chosen black and white points.