To create natural-looking colors and remove any color cast in your image, use the Automatic Color Balance command. This command works best for correcting images with several colors rather than images with variations of one color. You can apply the command to a selection or an entire image.
Important: These commands work on 16 million color images only. To increase the color depth of an image, see Increasing the Color Depth of an Image.
Choose Adjust > Automatic Color Balance.
In the preview window in the upper left portion of the dialog, center an important part of the image. Pan the image by dragging the cursor in the preview window. Zoom in or out as necessary.
Set the Strength of correction for the image, from 1 (the least) to 100 (the most). Start with 30 and then adjust the strength until the image looks the most natural.
If there is a strong color cast to the image (a particular color added to all colors in the image), mark the Remove color cast check box to remove it.
In the Illuminant Temperature group box, set the Temperature by entering a value or drag the slider to change the image’s illuminant temperature from warmer tones (oranges) to cooler tones (blues). The default setting is 6500K, which gives the effect of a photo taken in typical daylight. Photos taken indoors tend to look more orange, while photos taken in bright sunlight tend to look more blue. Adjust the value to achieve the desired effect or until the colors look the most natural.
Click OK to apply the correction.
Using Source and Target Colors to Correct Colors Manually
Using Greyworld to Adjust Colors