To help learn, I decided to paint my wall in Photoshop. I created a selection with the pen tool, new layer mask, new adjustment layer. I can use Hue/Saturation and change the colors. But what I can’t do is match a paint color exactly. For example, if I have this hex value, #6C6A66, how do I get the wall that color? If I do a color fill layer, it looks horrible, because well, it’s a fill layer, not an adjustment.
There’s a Photo Filter Adjustment Layer where you can put an Hex Color Number (at the middle of the image).
But is a Photo Filter, that depends on the result to get. I think a Color Fill Adjustment Layer with Color Blend is a good solution (At the left).
A good trick could be duplicating the Photo Filter Adjustment Layer (the central block of the image), the result is much refined than the Color Fill Layer: