Figs: you may consider trying the Mach Bands effect. It is not a color illusion, only a brightness illusion, but will work with a fast rotating top. We discussed that before on the old board (
see thread here). I obtained a good illusion with a pattern on the top of a top, but it should also work by painting the side:
The rotation of the top creates the necessary gradients, but the illusion itself is from the resulting static pattern so it can be seen in a photograph:
By the way, this pattern is very similar to the 4th one on the Naef Toys set, which is supposedly only about Fechner. It could be that a low speeds gives you one illusion while at high speed it gives you the other. I think I am going to bite the bullet and buy the set. Even if I can reproduce it, this will look nicer and be a great conversational piece.