Use PS calculations and channels to create alternative tones

final renderings

1. Open the original image, go to Image - Mode - Lab Color, and copy one layer.

2. Execute Image - Calculation, as shown below:

3. Open the channel panel, and we can find that the Alpha channel has been generated after the calculation just now.

4. CTRL+A selects all Alpha channels, CTRL+C copies, activates the a channel, and CTRL+V pastes.

5. Return to the layers panel, add a mask, and apply a black brush to the area where you want to retain the original color.

6. After merging the layers, change the image mode back to RGB mode to adjust the overall tone.

7. Before merging, you can also change the blending mode of the background copy and then merge it. Different blending modes will have different effects. The following is the effect after changing the overlay mode. You can also try the effects of other modes.