In your Levels Adjustments Settings Box, there are 3 sliders located underneath the levels histogram. To quickly correct your documents levels, move these sliders so that the black one lies at the far left of the tonal range, and the white one lies to the far right of the tonal range.
Excellent! You now have the tools needed for correcting improperly exposed photographs! Master these simple techniques, and you will become a pro at correcting your photographs in a matter of minutes!
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