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Color correct using the eyedroppers

You can use the eyedroppers in the Levels or Curves adjustment to correct a color cast such as an unwanted tint from an excess of color (red, green, blue, or cyan, magenta, yellow). It’s easier to color-balance an image by first identifying an area that you want to be neutral and then removing the color cast from that area. Depending on the image, you can use one or all three of the eyedroppers. The eyedroppers work best on an image with easily identified neutrals.

Note: The Set Gray Point Eyedropper tool  is used primarily for color correction and is unavailable when you work with grayscale images.

For the best results, don’t use the eyedroppers in images that require a large adjustment to map a pixel to the maximum highlight or minimum shadow values.

Important: Using the eyedroppers undoes any previous adjustment you made in Levels or Curves. If you plan to use the eyedroppers, it’s best to use them first and then fine-tune your adjustments with the Levels sliders or Curves points.
  1. Identify an area in the image that you want to be neutral gray. For example, a paved road.
    Use a color sampler to mark a neutral area so that you can click it with an eyedropper later.
  2. Click the Levels or Curves icon in the Adjustments panel, or choose Layer > New Adjustment Layer, and then choose Levels or Curves.
    Note: You can also choose Image > Adjustments, and then choose Level or Curves. You would complete the following steps in either the Level or Curves dialog box. But keep in mind that this method makes direct adjustments to the image layer and discards image information.
  3. In the Adjustments panel, double-click the Set Gray Point tool . In the Adobe Color Picker, verify that the currently selected color has identical R, G, and B values (for example, 128,128,128).
  4. With the Set Gray Point Eyedropper, click the neutral area that you identified in Step 1. This should reset midtones and remove the color cast from the image.
  5. If necessary, make final adjustments in the Adjustments panel.

    If you specified new target colors for an eyedropper, Photoshop asks whether you want to save the new target colors as defaults.