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Followup: Ultraviolet Vision After Cataract Surgery
xmas2003 writes "Several months ago, I posted to Slashdot about being able to see ultraviolet light after cataract surgery. While a lot of the discussion whimsically discussed the best way for 'Captain UV' or 'UltraMan' to use this 'super-power,' there were some people who were skeptical or (incorrectly) said this is Tetrachromatic vision. I've subsequently done more testing using an Oriel Instruments MS257 Monochromator and was able to see color down to 350nm — below the usual ~400nm limit of the visual spectrum. It's also easily demonstrable with a pair of 400nm and 365nm UV flashlights. Some readers who also have UV vision commented this can be quite annoying at black-lit Disney Rides, Halloween Haunted Houses, etc. Fortunately for me, it's just an interesting oddity so far. Along those lines, some interesting related stories about using UV vision during World War II and Star Gazing. Finally, many/most people end up getting vision debilitating cataracts, so my experience having a Crystalens implanted after cataract surgery may be informative."
Lando lost Cloud City in a game of Sabaac to a Hutt who had marked the cards with ultraviolet pigment.
An object has a color because it reflects the color and absorbs all others. So a red apple is red because it reflects red wavelengths. A black object reflects no wavelengths and absorbs all the visible colors. If you want to go attempt to claim that perhaps a black object reflects a spectrum that is non-visible to the human eye then this still doesn't help your cause. A theoretical object that absorbs all spectrum, including all non-visible wavelengths to the human eye, would still be black. Therefore, black is not a color, but the absence of color.