The Highlight/Midtone/Shadow command is useful to adjust selected regions of the tone scale. In this sense, the tone scale is divided into three general regions, containing light values (highlights), middle values (midtones) and dark values (shadows). The Highlight region is centered on the 75% tone, the Midtone region is centered on the 50% tone and the Shadow region is centered on the 25% tone. These three regions overlap somewhat in order to provide smooth transitions as the tone scale passes from one region to the next.
Important: To apply this command to a selection, the image must be a 16 million (24-bit) color image (otherwise the command is applied to the entire image). To increase the color depth of an image, see Increasing the Color Depth of an Image.
To use the Highlight/Midtone/Shadow command:
*Optional: To limit the adjustment to a specific area, first make a selection in the image. See Using the Selection Tools for more information on selections..
Choose Adjust > Brightness and Contrast > Highlight/Midtone/Shadow.
Select an adjustment method, either Absolute or Relative:
Absolute adjustment method: the controls are used to set the absolute positions of the 25% histogram point (Shadows), the 50% histogram point (Midtones) and the 75% histogram point (Highlights). Typical values are about 35 for Shadow, 50 for Midtone and 65 for Highlight, but they will vary depending on the particular image you have. Increasing the value will lighten the region and decreasing the value will darken it.
Relative adjustment method: the controls are used to adjust the lightness relative to their original state. Positive values will lighten the region and negative values will darken it.
Set the desired values for Shadow, Midtone, and Highlight.
Click OK to apply the correction.
Adjusting Individual Brightness Values
Adjusting the Brightness and Contrast in Unison
Adjusting the Lightness Levels
Correcting Images by Adjusting the Histogram
Manually Adjusting Brightness and Contrast