If the skin color is unified, there will be three problems, namely, the unity of lightness, saturation and hue of color elements. First of all, we should consider lightness, so we should use the black-and-white observation layer to make its tone at first, and it is no problem to see its tone in the black-and-white layer. At this time, we will find that the skin saturation will change a little and the color will change a little from hue. So you solve the problem of hue and saturation, and the colors are unified.

For example, this model, in order to have a certain effect, I draw one directly, but it cannot be too obvious. In the circle,

Our first step is to turn to black and white. I drew this one. I can see it in black and white, but anyway, we think it's ok for the time being.

At this time, we have to consider hue saturation. We will restore the color of the picture and click on the hue saturation. At this time, we will look at the color cast out and then restore it to the color of the skin. The color cast here is red. I drew it myself.

We choose red in hue saturation, and choose red instead of skin color, because the skin also contains this kind of red, and the red we choose is not really red, it includes orange and magenta. In the color part, we can see that the middle is red, one on both sides is magenta and the other is orange. At this time, we pull the slider of hue to the end.

It becomes 180, a bit like Avatar. This color matching technique is called Avatar color matching. At this time, we can see a lot of green and blue.

We must change the orange in the color section to red. At this time, the original skin color will slowly return to normal. There is no special color cast. We can control it properly and observe for ourselves. If it is too small, it will not play a role in color correction. The slider in this color section is to help us shield the problem of color cast.

Then we slowly pull back the hue from 180 and stop at about the same time.

At this time, if you think there is something wrong with the brightness, we can also adjust the brightness.

For comparison,

Let me talk about the principle of one first. Hue saturation can be intuitive, and hue saturation lightness has options. If you look at it from the observation layer, it is not a question of lightness, and saturation does not need to be considered. Then we need to consider what color this picture is cast. If it is red, after we choose it, there will be a range on its color segment automatically, which is similar to the feathering value, that is, it is softer when you slide the hue. We can narrow the color range of the color segment to accurately correct the color we need, and then move its hue. We pull it directly to 180 for better observation, and then narrow the color range, and we can restore it. What is not restored is color cast.