Adjusting Skin Tones

You might be thinking that I'm going to give you some kind of magic formula for creating great skin tones (kind of like what I did with grays), but if I give you just one formula, then every skin tone in nature's vast diversity would look identical in your images! I'd much rather show you how to get a unique formula for each color of skin you might run across—Asian skin, olive skin, sun-burnt skin, fair skin, and all the different shades of black skin. Even better, we can do all that without trusting your monitor at all. (Of course, they will still look good on your screen, but unless you've calibrated your screen using a hardware device, then you shouldn't make critical decisions based on your screen image.)

Literally dozens of companies, such as Stockbyte, sell royalty-free stock photography. If you call these companies and ask for a catalog of images, they'll be more than happy to send you a really thick book chock-full of images (it will either be free or they might charge you for shipping and handling). At the back of that book will be a CD that contains tiny versions of those images, complete with the stock photo company's logo slapped in the middle of it so you'd never use it for a real project. But we don't care about that, because right now we're after something else—most of them contain a veritable treasure trove of flesh that you can transform into your own personal stockpile of skin tones. So, flip through one of those wonderful catalogs, pick the person who has the skin tone that best matches your needs, and then open the corresponding image from the CD at the back of the catalog. Next, use the Eyedropper tool and click on an area of the skin that is a medium brightness (Figure 8.14). Now click on your foreground color to see the RGB formula needed to create that exact color.

Now let's figure out how to use that information to improve your image that contains skin tones. Open the image you need to correct and use the Color Sampler tool to click on the area that contains the troublesome skin. Be sure to click in an area with medium brightness, similar to the level in the other (stock photo) image. That should give you an extra readout in the Info palette (readout #1 if you just opened a fresh image, or readout #4 if you still have the three we used earlier in this chapter).

Next, click on the eyedropper icon that shows up next to that new readout in the Info palette. Choose HSB from the menu (Figure 8.15), note the brightness (B) setting, and then set that menu back to RGB. Now, click on your foreground color to look at the color from the stock photo again. We want to use that basic color, but we don't want to change the brightness of our image much. To accomplish that, change the brightness (B) setting to what you saw in the photo you are attempting to color correct and then write down the RGB numbers that show up in the Color Picker (Figure 8.16). In just a moment, we're going to use those RGB numbers to tell Curves how to shift the skin color in the problem photo to match the skin color in the reference photo.

But first, it's time to isolate the skin tones in your problem image and then make your adjustment. I usually choose Select > Color Range to isolate the skin. If you've never used it before, then be sure to read about it in Chapter 2, “Selection Primer.” Once you have a general selection of the skin (don't worry if it's not perfect), it's time to make the adjustment.

If the file you're working on already contains one or more adjustment layers (like the one we used for adjusting the Shadow, Highlight and Gray area earlier in this chapter), then make sure the top-most Adjustment Layer is active before continuing. Now, to start the adjustment, choose Layer > New Adjustment Layer > Curves. Then, to add a point to each of the red, green, and blue curves, hold Shift-Command (Mac), or Shift-Ctrl (Windows) and click on that same medium brightness area we sampled from earlier. Now, all you have to do is switch between the Red, Green, and Blue curves (use the menu at the top of the Curves dialog box) and type in the R, G, and B numbers you calculated and wrote down a few minutes ago (the ones you got from the Color Picker) in the Output of the Red, Green, and Blue curves. Once you've got the right numbers typed in, your skin tone should look much better (Figure 8.17).

Now that you've performed the adjustment, you should take a look at your image to determine if the selection you made earlier accurately isolated the skin. If you need to fine-tune where the adjustment applies, you can go back and paint on the layer mask that is attached to the Curves Adjustment Layer to control which areas of the image are affected. If you're not familiar with layer masks, be sure to check out Chapter 14, “Advanced Masking,” and Chapter 15, “Collage.”

The more you get accustomed to using this technique, the less you'll have to rely on that catalog for reference photos. You'll get used to knowing that the more red you pull out of your image, the more tan someone looks, and that the balance between green and blue determines the fairness of someone's skin.

If the skin-tone adjustment was a little too much for you to handle, then just start off by adjusting the highlight, shadow, and gray areas, and come back to this chapter after you've gotten comfortable with those. That might make it a little easier to understand and implement. The general concept is easy (and sneaky), but the execution isn't quite as simple as all that, because we have to make sure we don't mess up our earlier adjustments.