Some optical mixing goes on when you look at this painting I completed recently, and also subjective colouring that I think is more to do with after images than mixture.
Any blues and/or greens that you see here are subjective, you put them there optically. Physically any 'green' is yellow and any 'blue' is white.
We know about this stuff already. Maybe it is childish of me to continue to be so fascinated by these subjective constructions.