I was looking at a beautiful rainbow tonight and it occured to me. What would you see if you took a picure of a rainbow with black and white film… what about with a regular digital camera then changed it to black and white. What if you were totally color blind… what could you see? Obviously there is nothing physical to see other then light and color.
However, i know that if you take a b&w film pic of clouds in the sky, you dont see much but if you use a red filter the clouds look white and the sky black… so its sensitive to color somehow.