Next click on an area of medium brightness and double-click on the Foreground Colour at the bottom of the Toolbox. This will open the Colour Picker, allowing you to record the RGB (Red, Green, Blue) colour values, for example 203, 179, 78. Write these down and hit OK to close the dialog box.
The next step is to select the bad skin tone image, and select the Color Sampler tool which is stacked behind the Eyedropper tool. Again choose a selection range of 33 or 55 Average, and click again on an area of medium brightness. Now look at the Info panel and click on the small eyedropper arrow to change the color mode to HSB (Hue, Saturation, Brightness). Record the Brightness value, for example 76%, and reset the eyedropper arrow to RGB.
Now double-click on the Foreground Colour again. We wish to use this colour, but not its Brightness value. In the HSB section change the Brightness value to what it was two steps ago, and note the new RGB values (eg.192, 131, 73), and hit OK to close the dialog box.
Now in the problem image select the skin tones only and go into the Select drop down menu to Save Selection. Next add a Curves adjustment layer, and open the Red channel from the Channels panel to change the output to 192, thus adding a point on the curve. Go into the Green channel and change the output to 131, and the Blue channel to 73. Then hit OK.
Toggle the new adjustment layer’s visibility icon off and on to view the result, adjusting its opacity if necessary. You may remove a source point from the image by pressing Alt (Mac: Option) and clicking on the point. You can also adjust the layer mask with a black or white paintbrush. Feel free to add further adjustment layers as needed, for example a Hue/Saturation or Levels adjustment.
As can be seen, matching skin tones from one image to another is an easy matter in Adobe Photoshop, click here for more information.