Listen, I don’t know if you can appreciate this or not, I’m fully confident that some of you won’t be able to. Please hear me out before you pass judgement: I’m now using a program called DarkAdapted, which cuts gamma levels to preserve dark adaptation. Yes, all of the light emanating from my monitors is now red, but when I look away I can see with very little adaptation time. The software was originally developed for astronomers (who need to do stuff on their computers, then look in their telescopes).

Red is widely reported to be much less harmful to your dark adaptation than other types of light (such as white). The eye posesses the ability to increase its light perception ten billion times from full light to full darkness. Most people are aware that this happens by dilation of the pupil, but did you know that it ranges from 3mm to 7mm in diameter? That is an area increase of over 500% (really! do the math yourself). You may recall from some class forced upon you during your governmental education career that the eye has what are called rods and cones. Basically, the rods are responsible for light detection (vision in low light) and the cones are responsible for colors and detail. During regular light (like daylight), the cones are better at detecting things. After light drops below a certain point, the rods become better at detecting light. When graphed (as here), what’s known as the “rod-cone break” becomes apparent: the line between cones being better and rods being better. If you do that graph with specific wavelengths of light (blue, green, and red, for example), the curves are closest to each other with red (as here). That means that rods and cones detect red at similar levels, and your eyes don’t have to go through as much adaptation (which is the process of dilating your pupil and converting some chemicals which are slopped around inside your eyeball).

From that last graph, it also seems to me that eyes are most sensitive to ultraviolet light in the dark, i.e., that’s the kind of light you can see the best in the dark. Is that true? I can’t find any information offhand about it. Also, my analysis here may not be completely accurate – I shlooped it together hastily from a few different sites and I might have misinterpreted data in the process.

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