I regularly walk at night. I’m constantly surprised by my own senses. They’ll surprise you too if you give them the time to acclimatise and a little training. After a while artificial lights can be reserved just for safety on roads, difficult terrain or for carrying out tasks that just can’t be done in the dark. Here are five ways to improve night vision to start you off:
- It takes about 30 minutes for your eyes to acclimatise fully but most of this happens in the first five or ten minutes. The most simple way to improve night vision is don’t use any artificial lights and let your eyes acclimatise with the dusk.
- The eye has two types of photoreceptors – rods and cones. Rods are much more sensitive to light and are almost entirely responsible for night vision. Rods are concentrated around the edge of our retina. Take advantage of this and use averted vision in low light – don’t look directly at something but slightly avert your eye and you’ll be using the very light-sensitive rods.
- If you have to travel along roads with car headlights, meet someone shining a headtorch straight in your face or have to pass houses with security lights, shut one eye to avoid losing your night vision in both eyes.
- Walk with your eyes looking ahead rather than at the ground. You might want to practise this during the day first. You’ll soon get used to it. At night you’ll travel more quickly with your head up using your peripheral vision and feeling the ground with your feet.
- The rods in our retina have only one type of light sensitive pigment (compared to three pigments in the colour sensitive cones) so play little or no role in our colour vision. Tests have shown they aren’t sensitive to wavelengths longer than about 640 nm which equates to red in our vision. This means that using red light will have little or no effect on your night vision. If you need white light then use a very low intensity – as low as you can manage to read or carry out other tasks.
We tend to rely on artificial light more than we should. Work on some regular exercises to improve night vision. On a moonlit night you’ll be amazed at how quickly you can travel once you’ve become used to the light. Moving through the landscape without artificial light also makes us more a part of that landscape and in tune with all the other inhabitants who don’t have a 3 LED multifunction head torch stuck to them!