Impossible Colours

If you can combine the two crosses with your vision, you might have a chance of perceiving the impossible colour of Yellow – Blue.

I knew Impossible Colours existed.
Previously in my blog, I was thinking about colours.
I wondered if there were colours that humans could not process.

They are colour theories obviously, because it is difficult to prove colours exist that cannot be perceived.

Colours exist that are to complex to be perceived under regular light conditions.
They are only perceivable under special artificial laboratory conditions.