The Dodge and Burn tools are handy when you want to selectively darken or lighten a portion of your image. They offer precision control, too, because you can: (a) edit the brush size to better fit the area of the image you’re editing, (b) set the Exposure setting which changes the tool’s intensity, and (c) specify a value range, such as the shadows, midtones, or highlights. You can modify these settings on the tool Options bar, but an even quicker way is to learn the keyboard shortcuts.
Select the Dodge or Burn tool from the Tools panel. Press [ [ ] to decrease the brush size, and press [ ] ] to increase the brush size.
To edit the Exposure, you don’t need to highlight the text field on the tool Options bar, simply enter a value on the keyboard from 0-100. For a value of 1-9 percent, enter values as two digits, such as “02” for 2 percent.
To select which range you wish to target, press [shift][option]S ([Shift][Alt]S in Windows) to select Shadows, press [shift][option]M ([Shift][Alt]M in Windows) to choose Midtones, or press [shift][option]H ([Shift][Alt]H in Windows) to select Highlights.