Overexposure

• A photo is overexposed when lighting overpowers highlights and details. Overexposure can be used as a photographic technique, but it can also distort photographs in isolated areas.
  
  

Underexposure

• A photo is underexposed when shadowy areas are so dark that information is lost. Important details are concealed by shadows, but can be recovered.
  
  

Process

• Adobe Photoshop analyzes and redistributes light and dark values within the image to expose details concealed by light or shadow. The equalizing process can be achieved in several ways with Adobe Photoshop.
  
  

Importing

• Open the file in Photoshop if you already have a digital image. Or, import an underexposed or overexposed photograph into Adobe Photoshop by scanning the image, opening the software and selecting "Import" in the File menu.
  
  

Techniques

• Equalize an image easily with the "Equalize" command found in the "Image > Adjustments" menu. Select "Shadow/Highlight" if working with Photoshop CS. Another option is to right-click on your image in the "Layers" palette, select "Duplicate layer" then adjust the blend mode to lighten or soft light.