How many shades of colour can we see?

Did you know an iRochromatic (colour blind) person sees only about 10,000 to 100,000 different hues?  Those that are non-colour blind see about 1 million to 7 million different colour hues. However the human eye really only sees three colours. The retina has three types of cones; one is sensitive to the colour red, one is […]