Achieve greater control over exposure in Photoshop using the Color Range command
Open the Color Range command from the Select menu. Inside this is a drop-down called Select that contains options for selecting various parts of the image.
Set this to Shadows to select all of the dark parts of your image. All other options will grey out as Color Range has detected shadows across your image. Hit OK to exit the Color Range menu.
Add a Levels adjustment layer (Layer>New Adjustment Layer) and name it ‘shadows’.
Go back into the Color Range command and set Select to Midtones. Hit OK and apply another Levels adjustment, naming it ‘midtones’ this time.
Repeat this one last time for the Highlights option in the Color Range. You should end up with three Levels adjustment layers.
Adjust each Levels adjustment layer to balance exposure across the image for the highlights, shadows and midtone regions.
For a tip, be sure not to move the middle pointer in the shadows Levels adjustment.