Create monochromatic color in Photoshop
Step 1: Add a Solid Color fill layer above the image
The easiest way to convert an image to monochromatic color is by using a Solid Color fill layer.
In the Layers panel, the original photo appears on the Background layer. Add a Solid Color fill layer above the image by clicking the New Fill or Adjustment Layer icon:
And choosing Solid Color from the list:
Step 2: Choose a main color from the Color Picker
The Color Picker opens, and the image is temporarily blocked by whichever color is currently selected. By default, it’s black:
In the Color Picker, choose the color you want to use. At this point, we just need the hue (the main color). We’ll come back and adjust the saturation and brightness in a moment.I’ll choose a reddish-pink:
Click OK to close the Color Picker, and now the new color blocks the image:
Step 3 : Change the fill layer’s blend mode to Color
Back in the Layers panel, the Solid Color fill layer sits above the Background layer.
To blend the color from the fill layer with the image below it, change the fill layer’s blend mode from Normal to Color:
The Color blend mode keeps the tonal (brightness) values of the image below but replaces the original colors with the color from the fill layer, creating the initial effect:
Step 4: Re-open the Color Picker
The only problem, at least in my case, is that the saturation of the color is too strong, and it’s also too bright.
To fix that, re-open the Color Picker by double-clicking the fill layer’s color swatch in the Layers panel:
Step 5: Adjust the color’s saturation and brightness
And then adjust the saturation and brightness as needed.
I’ll lower the Saturation (the S value) to 30 percent and the Brightness (the B value) to 40 percent. Click OK when you’re done:
And with the saturation and brightness lowered, the effect is much more subtle:
And that’s the basics of how to convert an image to monochromatic color using a Solid Color fill layer in Photoshop!