View color values in an image

You can use the Info panel to see the color value of pixels as you make color corrections. When you work with a color adjustment dialog box or Adjustments panel, the Info panel displays two sets of color values for the pixels under the pointer. The value in the left column is the original color value. The value in the right column is the color value after the adjustment is made.

Using Levels and Info panel to neutralize the tone of an image

You can view the color of a single location using the Eyedropper tool . You can also use up to four Color Samplers  to display color information for one or more locations in the image. These samplers are saved in the image, so you can refer to them repeatedly as you work, even if you close and reopen the image.

Color samplers and Info panel