There's a lot of free data sets floating around the internet, and while things like funny cat videos and the
results of color-naming surveys get a lot of play, many others don't get used for much. Recently I've been playing around with one such data set: images from the
Airborne Visible/Infrared Imaging Spectrometer (AVIRIS).
I've always found it interesting that the way we perceive color is very different from how light actually works. Most of us have three different types of cones in our eyes and we perceive different colors as different combinations of stimuli to these three types of cones. In a very rough sense, when we look at a color, our brain gets three different numbers to figure out what it is. Light, on the other hand, is a bunch of photons with some distribution of wavelengths. To fully describe the light coming from an object you need a function that shows how many photons are at any given wavelength, which is way more complicated than just the three numbers we get.
So what about all that information that gets thrown away on the way to our brain? Are we missing out on a magical world of super-duper colors and wonder? Not really, but skip past the break anyways to find out more.