Ok. Or that sentence, the feeling can be the next look down, feel not how the drop of friends leave a footprint to other rooms to play.
See the original image, we first analyze the problem of this map out where. The classmate asked, how to analyze? Look at the information surface and histogram. These two things directly express the problem of this picture. OK, look at the picture.
Information surface I used the red box to place the RGB value of a person's skin. From which we can be very intuitive to see the low value of B, which is less blue in the picture, so the picture appears yellow. The classmate asked again, blue why yellow? Because yellow is the complementary color of blue. The first feeling histogram gives us is the darkened area of the most concentrated pixel, the middle harmonic and high light area is less.
After a preliminary analysis we can do it. We first set up a curve adjustment layer, first the picture to light up, and then initially adjust the relevant channel