I want this to kind of be a "mega thread" of paint.
So, here is the scenario: I have a room that I want to use as a studio. Since this room will only be used for photography, I want to have it painted in some standard colors. I'd like one wall 100% black, two walls 100% white, and one wall 18% gray.
Now, the idea is that I can rely on these walls instead of having a gray card. Yes, having a gray card would be easier and cheaper, but that is not the point of this question.
Can you give me a manufacturer and their color codes to create those colors of paint?
Edit: Original had 50% gray and not the correct 18%