A while back, I wrote about why there are no green stars in the sky (you should read that post first; some of the concepts below are explained there). But that’s not to say there are no green objects ...

Yes. A color filter’s purpose is to exaggerate differences in brightness, to increase the contrast between light and dark portions of the object under view. Consider, for example, using a blue filter ...

Colour vision is an integral part of the human visual system. It relies on the presence of three types of cone photoreceptor in the retina, which have different but overlapping wavelength tuning ...