I’ve always been interested in colour vision (yes, I’m in the UK, so US readers please translate: color); we have no way of really knowing how different people actually perceive differing hues. I once had an assistant who was extremely good at correcting colour casts when printing photographs, despite having a marked degree of red-green colour vision deficiency. I have a tendency to call green what others would describe as blue, and vice versa, but only in that rather ambiguous cyan/turquoise palette.
What we do know is that the way the cone sensors in our eyes work is fairly well-established and common to most people. We’ve all experienced afterimages after viewing a bright light source.
There is a rather more subtle example of the afterimage effect that results from over-stimulation of retinal cones on John Sadowski’s Blog. A description of how the false colour image is created is here and Wikipedia has a brief explanation of the phenomenon. A good example of why we should not always believe our eyes.
Posted by Roy Hammans in Seen on the web