As has been well-documented in recent days, I do not perceive certain colours - including red - in the same way as most people. Part of this means that I have a unique sensitivity to red light; I can consciously detect subtle changes that you are not aware of and I can even see beyond the visible spectrum of light. Because of the unique properties of red light (for example, Ferrari's rosso corsa is blood red so that it appears as intended on your television screen), you only subconsciously detect the full difference.