Nearing the completion of an on-going piece and I need to mix quite a large quantity of violet and white. Once mixed I don't want to use it all in one go, but need to return to complete. I don't want to try re-mixing another batch so to maintain the consistency in the shade. There will probably be several hours between uses.
I do use retarding gel occasionally, but it is only good for a few hours at the best. Or so I find
Any tips as to how I can store the paint in between and prevent it drying out? Airtight containers, jars, wet paper etc etc?
Any experience or assistance will be most appreciated