Change of color in cloth

[cathm]

Hi! I am wondering if it's possible to change both grandparents' clothes into black color.  

If yes, what is the best way to do this?

Thank you for your help in advance!

 

 

[Damien Symonds]

Granddad's, yes.  Grandma's, no.

[Damien Symonds]

The best you could do would be to lower the Lightness slider of a Hue/Saturation layer to maybe -65 or so, to darken it a lot.  The pattern would still be pretty apparent, though.