HOK Oriental Blue goes Purple
For reasons not worth going into, we have to paint over a dark, nearly black base. The resulting highlight blue is perfect with Oriental Blue Kandy, but the instant it goes off direct axis, it's completely purple. More coats makes it more intense purple, less coats just kills the blue.
Is there a Kandy that has that nice intense blue without the purple, or is there a way to compensate? We've tried several different black-ish bases (green black, red black, blue black, etc.) and it seems to make very little difference.