Sometimes people airbrush and beautify skin. But what if you want to do the opposite? This tutorial will show you how to use the yellow channel to create an intense skin effect that reveals skin flaws instead of hiding them. Although this effect is already available in the popular Skin actions, learning to do it yourself will make you understand how it works.
We are going to grab the yellow channel. But to do this, we need to switch to CMYK mode temporarily. Go to Image > Mode > CMYK color.
Go to your channels panel (Window > Channels) and then select the Yellow channel. Press Ctrl/Cmd+A to select the canvas then Ctrl/Cmd+C to copy the yellow channel to your clipboard.
Now we can switch back to RGB mode. But instead of doing it from the Image > Mode menu, press Ctrl+Alt+Z (Macs: Cmd+Option+Z) to undo until you’re back in RGB mode. You know you’re back in RGB mode when your Channels panel shows Red/Green/Blue instead of Cyan/Magenta/Yellow/Black. The reason we undo is because converting between RGB and CMYK mode will degrade your image. By undoing, you aren’t actually converting color modes back and forth.
Press Ctrl/Cmd+V to paste your clipboard as a new layer. Set the blending mode to Overlay.
Once you do this you’ll notice some areas, such as the eyes look dark. To bring it back up, add a Brightness/Contrast adjustment layer (Layer > New Adjustment Layer > Brightness/Contrast). Increase the brightness so that dark areas are revealed (in this photo, it’s the eyes).
Select the layer mask then press Ctrl/Cmd+I to invert it.
Press D to reset your foreground/background colors. Select the Brush tool (B) and then paint over the eyes or anywhere that’s too dark to brighten it back up.
That’s it! Here is how it looks like before and after. This is a very common trick to intensify skin and unbeautify it. If your person has freckles, it will even bring out the freckles.