I have a large living room that is currently painted a dark green. The plan is to change the color to a very light blue. I have a Sherwin Williams latex satin paint sample for a blue that is too strong. Can I use some of this as a tint in a latex primer, to help cover the green? Can I use it to give a bluish shade to a white paint that I use as a top coat, for example a Sherwin Williams Duration or Harmony extra white? I'm thinking of using an eggshell finish on the top coat, if that matters.
As long as the sample and the paint/primer are both the same type, i.e. latex or oil, you can mix it in with no real problems. Depending on the size of the sample it may not do much. It won't be as strong as pure pigments that go in the product from a colorant dispenser. I don't see a problem doing this on your primer if you want to. I wouldn't try it with the topcoat. If you get a color you like out of it and end up with not enough product then you have to try and match your homemade mix, which never comes out perfect.