Periodically it pops up that people are perpetually confused about the rainbow eyes. People think there's only one or two or think one is the other
etcetera.
Rainbow Eyes LABELED
Here you can see that Prismatic is the fundamental base eye. It is the brightest and cleanest of the lot. Rainbow Prism is identical except that it is less saturated and some delicate shading and feathering has been added.
Odyssey Rainbow is a different kettle of fish (and not just because it's shown curious big here). If you look very carefully on the right (which is the toyger's left eye) you can see that Prismatic is still the basis of the eye - look at the yellow at the bottom. However additional heavier colors have been added in a second layer. It has a kind of tomato red and a darker green and other additions like a strong strip of blue (on the toyger's right eye).