How to see a redder red

ananyo writes: When Bob Marley sang, “I am redder than red,” he probably did not imagine that chemists would one day capture this imagined hue. But researchers have taken a step in that direction, by tweaking a colour-sensing pigment from the human eye to absorb reds of longer wavelengths than those that we can see.
The researchers’ red was the product of experiments conducted to understand exactly how colour-sensing pigments in our eyes absorb different hues. The team targeted rhodopsin, a pigment found in the photoreceptor cells of the retina. Their engineered pigment had an absorption peak at 644 nm — far redder than a natural red-sensing rhodopsin, which has an absorption peak at roughly 560 nm) would 'see' 9abstract of paper in Science).