Yaaay...it's back.
Do You See What I See?
Roses are red, violets are blue but according to the latest understanding these colours are really an illusion. One that you create yourself.
Horizon reveals a surprising truth about how we all see the world. You may think a rose is red, the sky is blue and the grass is green, but it now seems that the colours you see may not always be the same as the colours I see. Your age, sex and even mood can affect how you experience colours.
http://www.bbc.co.uk/science/Not sure if BBC content is available outside of the the UK.
Do any other countries take the programme, by the way? I know, when I was a kid, the BBC used to produce Horizon in association with WGBH in Boston.
Not to worry. There are instruments which give the actual frequency ranges of visible light.