Body Hack: How to See in the Dark (Like Pirates!)

Chances are good that you, like me, have always assumed pirates wore eye patches because their eyes were poked out in a vicious swordfight on the high seas. It’s a brutal life, that. Arrrrrrgghhhh. But it turns out we may be wrong about our seafaring friends. Pirates, some people believe, simply figured out a way to see in the dark.

Take a lesson from the pirates, and you can too.

Your eyes can see things across a very wide range of light levels. Obviously, for most of us, our eyes work pretty well when the sun is up or the lights are on. But if the lights go out, we go blind—for a moment.

This was a pretty inconvenient situation for a pirate running up and down between decks. The eye patch, it’s rumored, fixed that. When ducking into darkness beneath the deck, the savvy pirate would simply switch his eye patch from one eye to the other. The eye that was previously covered by the patch, and in the dark, was immediately adjusted. No more fumbling pirate!

(Important note! The Mythbusters took a look at this rumor in 2007 and deemed the myth “plausible.” The night vision experiment pretty much checked out, but was lacking historical precedent. But pirates aren’t the only ones. The FAA recommends that pilots “close one eye when using a light to preserve some degree of night vision in the cockpit” in one guide posted on the agency’s website)

But don’t let those pesky pirates tell us how to live our lives. You can try this body hack at home, too.

Here’s what you do.

Hop in bed with your iPad or iPhone and turn the brightness all the way up. Close or cover one of your eyes, and have somebody hit the lights. Now stare at the bright screen for a few minutes, giving your open eye plenty of time to adjust to the glare. Make sure to keep that other eye closed! After a couple of minutes, put down the iPad and look around the room with the eye that is already open. You’re blind! Now, switch. Open the eye you had closed and close the eye you had open. If you did it right, that other eye is already adjusted to the darkened room, and you can see.

Night vision.

This period of temporary blindness is what researchers refer to as “dark adaptation,” which is measured by tracking how quickly the eye recovers in the dark following its exposure to a bright light. It happens as your eye is busy regenerating photo pigments, and can take upwards of 25-40 minutes to get back to normal.

Those are crucial minutes no pirate—or bed-seeking midnight fumbler—should spare.