To respond a little - I was trying to use "innately get depressed when not exposed to sunlight" as an example of something well researched showing that light affects people physically in ways that are not just 'seeing shape and contrast' (which sillysaurus' post seemed to be stating was the be-all and end-all of colour and vision).

Its a slightly different point to 'enjoying colour differences', which of course we do. Compare a sunset in real life (even behind a window) with that in a photo - for instance....

>To respond a little - I was trying to use "innately get depressed when not exposed to sunlight" as an example of something well researched showing that light affects people physically in ways that are not just 'seeing shape and contrast'

It could not be light as such though. It could be warmth from the sun that makes people depressed when not exposed to sunlight, or vitamin deficiency (some vitamins need sunlight to be usable).