I have an animal within who can see at night. And so do you. Humans have a setting on our eyes we use but rarely pay attention to: night vision.
This winter, I set out to create another optical effect: a lit candle that brightens as the eyes adjust to the dark. The effect– a demonstration comparing our two types of vision rather than a true illusion–works because our night vision sees color differently, allowing a camouflaged flame to emerge in contrast.
LIGHTS OFF, EYES OPEN
It takes 45 minutes in near total dark for human eyes to totally adjust to night vision: a black and white, grainy world.
In this age of electricity, most people do not experience real darkness, with eyes open, for 45 minutes. We are often partially adjusted, where colors are present but muted.
THE NIGHT CREATURE EMERGES
One dark night last spring, I found myself walking along the California coast, in a housing development engineered decades ago to be an eco-friendly utopia with no light pollution. After an hour, the trails and roads seemed lit brightly, everything was in black and white, and if I looked directly at something, it would disappear—a dead giveaway of night vision’s preference for the peripheral.
Returning home, I was excited to learn more about this hidden set of eyes, and looked for chances to use them again. I learned that our night vision eyes are not only black and white, but what is red in daylight red becomes black, and blue brightens.
I photographed colored markers to simulate the night vision transition to black and white. Look closely and you can see this color shift: the red is as dark as its neighbor black and blue is lighter than its neighbor yellow.
A COLOR PIRATE
After about six months of looking for a chance to experience 45 minutes of total darkness “in the wild”, I realized how hard it was to escape light pollution.
I could filter red my phone’s screen or my own flashlight—since red goes black, a dim red light won’t ruin night vision—only to encounter the flashlights of others. A passing car. A stray landscaping light. It all sent me back to square one.
So I took the operation indoors. This not only guaranteed my eyes would adjust without interruptions, but I could create red and blue pictures to entertain my night vision, ensuring that after all the waiting, it would have something interesting to look at.
I made a dark room out of blackout curtains, set a timer for 45 minutes, and waited as a black and white, eerie version of the room emerged from the pitch black, as if out of fog.
Once was enough: I couldn’t wait 45 minutes to test each drawing. So I used an eye patch to allow one eye to always be adjusted (pirates, who had to be ready to see below deck, probably used them for the same reason).
It worked: after removing the eye patch in the near dark, the drawing transformed from a nearly unlit candle to one with a bright blue flame in semi darkness, and a bright white flame in near total darkness.
The shift in tone was so unmistakable that I had a false memory of using a sky blue marker for the candle flame instead of the darker blue.
Even though I knew what would happen, it still felt like a magic trick to turn the light went back on and watch the “real” colors instantly flood back into the drawing.
It’s crazy how much effort it took to experience night vision. City light pollution is notorious for obscuring huge numbers of stars that would otherwise enchant long winter nights. But chasing night vision showed me the smaller scale: our own personal light pollution we bring inside houses and into rural areas, so constantly that we’ve literally forgotten about one of our senses.
What if people became so attuned to night vision that everyone had one room that could go totally dark at any time? I hang up the drawings in my own blacked-out room, a light pollution escape pod darker than my bedroom ever gets. The camouflaged blue flame hides one that burns white against the darkness, unlocked only by the nocturnal animal within us.
Photo and Drawings by Emily Wick