Neutral color is relatively quiet color, there are many color matching methods, you can reduce the saturation of the picture, you can also use channel replacement to tune. The method is different, but the basic idea is consistent, first want to pull out the main color of the picture, and then reduce the color brightness.
Photoshop Tutorial artwork
< small map view big picture >
Final effect
1, open the material picture, press CTRL + J to copy a layer of background layer. Enter the channel panel, select the green channel, press CTRL + A all, press CTRL + C to copy, select the blue channel, press CTRL + V to paste. Then point to the RGB channel, and then return to the layers panel, the effect of the following figure.
< map 1>
2, create hue/saturation adjustment layer, red, green adjustment, parameter settings such as Figure 2, 3, the effect is as Figure 4. This step of the picture in the red and blue color into a unified orange.
< map 2>
< map 3>