Specific Replace One Colour With Another

[Cosworth69]

Hi,
I'm trying to change the groves in the leather material below from black to blue (sample of the blue also below). I can't figure out how to select just the black grooves in order to change their colour or find a tutorial regarding the issue. Any edit would be much appriciated.

Many Thanks,

 

[Dennis1507]

I tried masking out the dark areas. Then put your purple color layer under it. It turned out looking almost black. It is the requested color. It shows up if you zoom in. The second image I attempted to increase the purple color intensity to bring out the desired color in the overal image. Let me know if this is what you had in mind.

 

[Babine]

I used light and dark selections to start and used these as alpha channels to apply your colour; various luminosity masks and curves adjustment layers for contrast and saturation.

 

[HuckinFell]

Applied a "Photocopy" filter, used "Select by colour" tool to select and delete the white and then colourised the remaining lines to the desired hue.

I then laid that network of blue lines over the original image and tuned the opacity down and they saturation up to get this result: