The ninja must be able to see in near darkness to excel in stealth.
The eyes have two types of cells that enable us to see. They are the cone cells and the rod cells. The cone cells see colour and works better when it is bright, whereas the rod cells can see in low light and detect movement. However, it takes up to 30 minutes for the eyes to adjust to the dark.
That said, there are human limitations to this technique to see in the dark.
3 Steps to Natural Night Vision
1. Allow your eyes to become accustomed to the dark
You can do this by closing your eyes for 10 seconds and then opening them when you first encounter a dark environment. If this is impossible to do, you can either squint both eyes or cover one eye before you enter the dark area.
2. Use your peripheral vision to see
Your direct vision utilises cone cells, which is better at seeing colour in good lighting conditions. However, if you need to see in the dark, use your off-center vision. Look at the environment with the side of your eyes.
You can do so by looking 5 to 10 degrees above, below, or sides of the object.
3. Scan and blink to ensure optimal night vision
Within 5 to 10 seconds of focusing on one point of your peripheral vision, the visual will fade out. Your eyes will become less sensitive to the visual. Therefore scan the area constantly or blink to make sure that your rod cells don’t become desensitised.
What if you need to read a map in the dark?
If you need to read a map, you’ll obviously need some form of light. It is preferable to use moonlight or natural light. However, if this is insufficient, use low-intensity red light for map reading in the dark; the type of light you use can affect your night vision temporarily. Red does not affect your night vision as much as white light.
Note that you should use proper lighting for regular reading (at home). Don’t be ridiculous and use red light for regular reading. You will spoil your eyesight.
If you truly want to harness your night vision, practice a few times each week by moving around in the dark. Choose a place safe and familiar to you (your house/backyard). You do not want to be attacked by a wild animal or criminal while training.
There are also artificial ways to night vision, which we will cover later.
Updated 8 Feb 2014