The Dodge tool and the Burn tool lighten or darken areas of the image. These tools are based on a traditional darkroom technique for regulating exposure on specific areas of a print. Photographers hold back light to lighten an area on the print (dodging) or increase the exposure to darken areas on a print (burning). The more you paint over an area with the Dodge or Burn tool, the lighter or darker it becomes.
Applying the Dodge tool or Burn tool to the background layer permanently alters the image information. To edit your images nondestructively, work on a duplicate layer. For information on duplicating layers, see Layer basics.
Select the Dodge tool or the Burn tool .
Choose a brush tip and set brush options in the options bar.
In the options bar, select one of the following from the Range menu:
Changes the middle range of grays
Changes the dark areas
Changes the light areas
Specify the exposure for the Dodge tool or the Burn tool.
Click the airbrush button to use the brush as an airbrush. Alternatively, select the Airbrush option in the Brush panel.
Select the Protect Tones option to minimize clipping in the shadows and highlights. This option also tries to keep colors from shifting hue.
Drag over the part of the image you want to lighten or darken.