The original image in the tutorial has a relatively single color, so you can adjust it separately when adjusting the color. It is best to adjust the background color to a somewhat contrasting color. This way the characters appear more distinct.
Original picture
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final effect
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1. Open the original image material, press Ctrl + J to copy the background layer, change the layer blending mode to "Screen", and change the layer opacity to: 50%, the effect is as shown in Figure 1.
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<Figure 1>
2. Create a gradient mapping adjustment layer. The color settings are as shown in Figure 1. After confirmation, change the layer blending mode to "Color Burn" and use a black brush to erase the character part on the layer mask. The effect is as shown in Figure 3.
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<Figure 2>
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<Figure 3>
3. Create a curve adjustment layer. The parameter settings are as shown in Figure 4-6, and the effect is as shown in Figure 7.
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<Figure 4>
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<Figure 5>
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<Figure 6>
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<Figure 7>
4. Create a new layer, fill it with color: #010333, and then change the layer blending mode to "Exclude". The effect is as shown in Figure 8.
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<Figure 8>
5. Create a brightness/contrast adjustment layer. The parameter settings are as shown in Figure 9, and the effect is as shown in Figure 10.
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<Figure 9>
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<Figure 10>
6. Create a new layer, stamp the layer, and simply skin the character. The effect is as shown in Figure 11.
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<Figure 11>
7. Create a new layer, stamp the layer, and simply use the burn/dodge tool to deepen the outline of the character’s facial features, as shown in Figure 12.
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<Figure 12>