This might sound like the premise for a porno (bow chicka wow wow) but it’s really about how your eyes work in darkness.
Your eyes use cones for color and fine detail. Rods on the other hand see only in black and white, but they’re a thousand times more sensitive to light. Oh, and there’s about as many of them as there are Twilight fans. About 120 million of them. And at night, much like Twilight fans, they can’t see color or detail or see what’s right in front of their faces. And I’ll explain why. Rods take a lot longer to adapt than cones, so your night vision is not instant. It will take your eyes 45 minutes to gain complete night vision, which coincidentally is about as long as it takes for Viagra to kick in. The worst time for night vision, unlike Viagra, is dawn or dusk. It’s this transitory period where your eyes begin switching over from cones to rods and vice versa. Your rods actually prefer moonlight. The rods in your eyes, that is. They pick up motion well, but they’re not so great at detail.
1. Scan and tilt
Once night vision kicks in, you might wonder why you can spot a corn chip on the ground from the corner of your eye and then fall over a table right in front of you. That’s because you’re stupid. No, but seriously. That’s because rods are located further out from the center of your retina. This is your night blind spot.
So if you want to survive at night, you need to employ a method commonly used by soldiers to detect things at night. Other than night vision goggles. Turn your head side to side and up and down. You can use this method to identify something or someone without looking directly at it. As soon as you look directly at it, you’ll encounter your night blind spot. If you’re in a situation where you’re at risk of being detected, then move your eyes from side to side instead of your head so you don’t give away your position.
2. You’re not a moth, stop looking at bright lights
Looking at bright lights – a street lamp, car headlights, a UFO about to abduct you – is a natural reaction. Fight it. As soon as you look directly at a bright light … bye bye night vision. Then you’re back at square one and you’ll have to spend another 30-45 minutes adapting to the dark again. Some lights will blind you more than others. On the least blinding edge of the spectrum is red light. The military use red lights when operating at night. Ship captain’s instruments are lit with red light. This is not because their favorite color is red, it’s because your rods are not very sensitive to red light. The center of your retina, the fovea, is packed full of red sensitive cones. It also happens to be the same area that has no rods. This is why using a very low intensity red light does not destroy your night vision. In fact, pilots are known to wear red-tinted glasses in low light conditions if they don’t have time to sit in perfect darkness prior to night operations. The rods in your eyes are most sensitive to blue-green, like the green of a traffic light or the blue of a car headlight. If you don’t have time to stop a bright light destroying your night vision, cover one eye. You see? The pirates were onto something!
3. Approach concealed areas from a wide angle (that’s what she said?)
If everyone did this in movies, no one would ever get kidnapped. And there would be 63% less karate chops. Giving ye dubious abode a wide berth is critical at night, when you need every sliver of a second for your reaction time. If you’re walking down a street and you’re sticking close to the shop fronts, you’ve become an easy target for an opportunistic assault from an alcove, doorway or alleyway. Or even just a simple corner. It’s about as smart as pointing a gun at someone who is within arm’s reach – don’t do it unless you want to be disarmed, or at least attacked.
- Put as much distance between you and potential hiding places
- Walk curb side to see into alcoves and doorways before it’s too late
- Walk on the opposite side of the street to streetlights for safer, more even lighting (unless you’re a deadly ninja assassin trying to conceal yourself, in which case stick to the shadows)
- Take corners as widely as possible
- Check corners for shadows – does that lamppost have a shadow? Yes? Is there a human shadow next to it? How far away?
4. Does eating carrots improve your night vision?
No. This is a myth that originated from a British disinformation campaign during World War II to throw Nazi Germany off the scent of their new radar technology. If you’re suffering from Vitamin A deficiency then your night vision is likely to be poor. Red meat, eggs and liver are rich sources of Vitamin A (retinol) that can help recover your night vision. Vegetables and fruits have smaller amounts, but are helpful.
5. Does squeezing your eyes tightly improve your night vision?
This is a common myth in special forces: squeezing your eyes tightly for several seconds prior to entering a dark environment will boost your night vision. This appears to have a mostly psychological effect. Closing your eyes will certainly kick your night vision in, but you’ll still need to wait 30-45 minutes to attain full night vision. Squeezing them won’t speed things up.
6. Does eating sugar cubes improve your night vision?
The myth goes that Soviet soldiers would eat sugar cubes, claiming that sugar feeds the optic nerves, and then expose themselves to red light for ten minutes. Um, yeah. Red light is a means to minimize loss of night vision, but it certainly won’t improve it. Vitamin B1 is actually a nutrition source of the optic nerves. If you eat a bowl of candy, the body uses up Vitamin B1 and voila – Vitamin B1 deficiency. This gives you eye fatigue and messes with the function of your optic nerves. Which could explain why 60% of Americans wear prescription glasses.
7. Check yourself before you wreck yourself
I just wanted a cool way to say “check if you’re being followed”. That’s the best I could think of.
- Can you see the shadow of the person behind you? Under streetlights a person’s shadow can run ten meters long.
- Know a house with a dog that barks at passers by? Good, walk past it. Then listen out to see if it barks again.
- Walk out of step on purpose. If someone is trained to follow you they’ll synchronize their footsteps with you.
- If you look at your suspected tracker/stalker/ex-boyfriend and they immediately stop walking or change direction, they are a) following you and b) also an idiot.
- Use distance to protect yourself. This is pretty obvious. As soon as you’re out of sight, get some distance between you and your tracker.
- Look for shine on their skin, this is an excellent way to identify someone in darkness.
- Is your suspected tracker walking at the same pace as you? This is usually a key giveaway.
- When trying to identify someone in the dark who may or may not be there, your brain will try to recognize a face first, then it will attempt to recognize a human-shaped body. If it fails at this, it can often make shit up.
- If you can’t see the tracker following you and you don’t want to arouse suspicion, purposely drop something and almost walk past it. This gives you an excuse to turn around and crouch to pick it up. While crouched, your tracker can be more easily identified if they are backlit by a street light or the moon. Remember, your night vision works on shapes and outlines, not color or detail.
8. Survive an attack at night
- If you’re walking on a footpath and someone ahead of you is standing near the curb to force you in towards the shop fronts, don’t. Cross the street or walk around them on the curb. You do not want to be boxed in and set up for an ambush.
- A valuable tool to carry with you is a torch. You can use it to shine in your attacker’s face and blind them. It will take your attacker at least ten seconds to gain enough vision back in order to chase you, let alone see you. Use those ten seconds wisely. Either escape or disable them.
- Don’t run if you can’t see in the darkness. The last thing you need is to run head-first into a brick wall and knock yourself unconscious. You’ve just made a mugger’s job somewhat easier.
9. How to Walk While Blind (Not the Drunk Kind)
- Hold one palm out at waist height and keep it there.
- Wave your other hand up and down in front of you, brushing from head to waist height. It might look like a slightly deformed swan dance, but it works.
- Take short, slow strides. This is the only time you should be walking with the heel (as most people do anyway). Test each step with the heel before committing. Keep your weight on your back foot. This is handy if you encounter a flight of stairs and don’t want to break your neck.
Okay now you’ve absorbed all that, get on over here and learn some more survival skills. Just in case you ever find yourself in the situation where you wake up and discover you’re a deniable operative.