I have the notion I have invented a meditative new practice. I’m going to call it scotopic bathing because it involves taking a bath in the dark. No candles. No bulbs. No cell phones. Just the dim seepage of light from beyond the door, or from outside the window.
If you’ve been following along ,you’ll know my last two posts pertained to scotopic vision, or the ability to see in the dark thanks to the power of the rod photoreceptors on our retinas. What most people don’t know is that humans have the ability to see in the dark (albeit somewhat poorly when compared with say a deep sea fish or an owl).
The trick is to allow your eyes to adjust. It’s supposed to take about 20 to 30 minutes, and if you really want to see more detail, given you have more rods on the periphery of your eye and not near the center (the fovea, which is mostly cones), you can even try hacking it by examining the thing you want to see in the dark from the side of your eye.
Why did I do it? Well, call it mad scientist curiosity. I wanted to experience the change. Of course, when I initially turned the lights off and guessed my way into the bath tub, I was a little alarmed. The room felt entirely black and as I dipped my ears below the surface, a very real feeling of sensory deprivation kicked in. When the sound of my blood pumping got to be too much, I lifted my head out of the water and focused on trying to make out shapes.
At first I didn’t see anything. Then, slowly, as the minutes ticked by, raw edges became visible, though it felt like I was only seeing them for seconds before they blipped out of existence. The edge of the wall alongside the bath tub, the cabinet running the length of the room, maybe the shower railing above.
It wasn’t until a few minutes more that other details shifted into sight—the tap, a collection of shampoo and soap bottles, the shower curtain, the rod. And still, as I lay there taking it in, more began to appear and it felt as though light were suddenly coming in.
Startled, I wondered if perhaps a flood light had turned on outside, or if more lights were on in the hall. But, as I lay there and nothing else changed, and as I grew further accustomed, I realized I was experiencing true scotopic vision.
I tested my side eye abilities too and sure enough it was easier to make out more detail (albeit all in black and white) of plugs, razors, and more, all thanks to that periphery glance. A straight on glance sent things blurring back into the mist.
I decided to prolong the experience and do my hair as well as shave in the dark. It was far easier than expected. Though I didn’t get much more out of it than getting to experience science in action, I felt energized by the fact that I could put some of my learnings to the test.
The whole experience made me wonder about other things too: could a dimmer dive light on a scuba dive, encourage more close-up interactions with marine life? Are all fish and invertebrates really light sensitive? And, is that why our blackwater dive guides in Hawaii, jetted out to drop us to hand 5,000 feet over the depths in the dark? The captain hadn’t wanted any lights on on the boat. Was it so his vision could adapt? And surely we too should have dived dimmer lights on these pelagic dives? Might that have helped those skittish critters? I recall now a squid smacking me in the arm. And in fact, the same thing happened to me when diving RMS Rhone in the British Virgin Islands. One night dive on the Rhone, a shoal of squid shimmered by and suddenly, within quick succession I’d felt a couple of hard punches on my body. Lesson learned. Lights not loved by squid!