Shadow/highlight command options – Adobe Photoshop CS4 User Manual

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USING PHOTOSHOP CS4

Color and tonal adjustments

Last updated 1/10/2010

Make sure that the Preview option is selected in the dialog box if you want the image to be updated as you make
adjustments.

Adjust the amount of lighting correction by moving the Amount slider or entering a value in the Shadows or
Highlights percentage box. Larger values provide either greater lightening of shadows or greater darkening of
highlights. You can adjust both Shadows and Highlights in an image.

For finer control, select Show More Options to make the additional adjustments.

Note: To increase shadow detail in an otherwise well-exposed image, try values in the 0-25% range for Shadows Amount
and Shadows Tonal Width.

(Optional) Click the Save As Defaults button to save your current settings and make them the default settings for
the Shadow/Highlights command. To restore the original default settings, hold down the Shift key while clicking
the Save As Defaults button.

Note: You can reuse Shadow/Highlight settings by clicking the Save button to save the current settings to a file and later
using the Load button to reload them. For more information on saving and loading settings, see “

Click OK.

Shadow/Highlight command options

Amount

Controls (separately for the highlight and shadow values in the image) how much of a correction to make.

Note: Extreme Amount values may lead to a crossover, where what started as a highlight becomes darker than something
that started as a shadow; this can make the adjusted images look ‘unnatural’.

Tonal Width

Controls the range of tones in the shadows or highlights that are modified. Smaller values restrict the

adjustments to the darker regions for shadow correction and the lighter regions for highlight correction. Larger values
increase the range of tones that are adjusted further into the midtones. For example, at 100% the shadow tonal width
slider affects the shadows the most, the midtones are partially affected, but the brightest highlights are not affected.
Tonal width varies from image to image. Too large a value may introduce halos around dark or light edges. The default
settings attempt to reduce these artifacts. Halos may also occur when the Shadow or Highlight Amount values are too
large.

Tonal Width is set to 50% by default. If you find that you are trying to lighten a dark subject but the midtones or
lighter regions are changing too much, try reducing Shadow Tone Width toward zero so that only the darkest regions

are lightened. If, however, you want to brighten the midtones as well as the shadows, increase Shadows Tonal Width
toward 100%.

Radius

Controls the size of the local neighborhood around each pixel. Neighboring pixels are used to determine

whether a pixel is in the shadows or highlights. Moving the slider to the left specifies a smaller area, and moving it to
the right specifies a larger area. The optimum local neighborhood size depends on the image. It’s best to experiment
with the adjustment. If the radius is too large, the adjustment tends to brighten (or darken) the whole image rather
than brightening the subject only. It’s best to set the radius to roughly the size of the subjects of interest in the image.
Experiment with different Radius settings to obtain the best balance between subject contrast and differential
brightening (or darkening) of the subject compared to the background.

Brightness

Adjusts the brightness in a grayscale image. This adjustment is available only for grayscale images. Moving

the Brightness slider to the left darkens a grayscale image, and moving the slider to the right lightens a grayscale image.

Midtone Contrast

Adjusts the contrast in the midtones. Move the slider to the left to reduce the contrast and to the

right to increase the contrast. You can also enter a value in the Midtone Contrast box. A negative value reduces
contrast, and a positive value increases contrast. Increasing midtone contrast produces greater contrast in the
midtones while tending to darken the shadows and lighten the highlights.