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Adjust color using Levels

  1. Do one of the following to access the Levels adjustment:

    • In the Adjustments panel, click the Levels icon  or a Levels preset, or choose Levels from the panel menu.

    • Choose Layer > New Adjustment Layer > Levels. Click OK in the New Layer dialog box.

      Note: You can also choose Image > Adjustments > Levels. But keep in mind that this method makes direct adjustments to the image layer and discards image information. Settings are adjusted in the Levels dialog box.
  2. In the Adjustments panel, do one of the following to neutralize a color cast:

    • Click the Set Gray Point Eyedropper tool . Then click in a part of the image that is neutral gray.

    • Click Auto to apply the default automatic levels adjustment. To experiment with other automatic adjustment options, choose Auto Options from the Adjustments panel menu, then change Algorithms in the Auto Color Corrections Options dialog box.

    In general, assign equal color component values to achieve a neutral gray. For example, assign equal red, green, and blue values to produce a neutral gray in an RGB image.