Can humans see in low light conditions?
Yes, better than we can imagine but before replying, it is important to stress some facts about the scotopic vision (night vision):
- No one can see in complete darkness – There are a lot of ways to “manage” the dark but, as long as we speak purely about optical impulses, if there is no light, nothing is recognizable
- We see through the photons that hit our eyes – On a sunny day upwards of 100 million times more photons are available to our photoreceptors than a cloudy, moonless night
- Not only fewer photons – In addition to drastically decreasing in number, another problem is that, in low light conditions, photons hit the human eye in a less reliable way
- We cannot reach the cats’ level of light capturing – Cats’ pupils are elliptical and vertically oriented so they can open up much more, this way a bigger amount of light is captured (this gives them a 6-8 times better night vision)
- Our eyes are not fast in adapting to low light scenarios – While the regulation of the pupil in intense light is almost instantaneous, we need each time about 20-45 minutes to accustom our sight to the darkness (at its maximum level of quality)
- There are limits that cannot be overcome – Again, in terms of pure sight, our ability to adapt to the darkness depends on factors that are beyond our control, such as age, previous eye injuries and / or the presence of eventual diseases
A note by Master Kongling – The cat’s night vision is similar to the one in a slight desert storm, it is larger but not clear as ours (moreover, cats cannot see the red colors and they have difficulties to see far). Another peculiarity of the cats is that they have a structure made of mirror-like cells containing crystals behind the photoreceptors (the so-called Tapetum Lucidum) that gives them a second chance to detect the photons (it is for this reason that their eyes “light up” at night).
How to improve the night vision
Here are some simple tricks to get (and do not miss) the night vision:
- How to prepare the eyes – If we know that we will need it, let’s prepare our eyes tightening them for about 20 minutes
- If we do not have 20 minutes – We can wear glasses with red lenses (as the aviators do in night flies)
- Avoid the light sources – Let’s never look directly at the sources of light directly; if we cannot avoid it, let’s at least cover one of the eyes
- Let’s use the overall view – If we maintain the sources of light far from the area we are focusing the night vision will not reset
- How to increase the night vision – Each time we do not have to look at something specific, let’s look at the darker area of the scenario, this way we will recover / improve it
- How to avoid intense exposition – If possible, let’s use our hands to protect your eyes from the sources of light (sometimes it takes little to effectively mitigate light spraying)
- How to avoid the 90% of lights – To do not get caught by an unexpected light source (eg. a flashlight), let’s tend to look down so as not to be caught out by unexpected lights
- How to recognize the forms in the dark – Let’s assume a stance as lower as possible, this way we can use the skylight as a contrast to recognize the silhouettes
A few conclusive thoughts:
- As Ninjutsu teaches us, patience is the first skill, when we talk about stealth capabilities, if we lose the night vision (and the situation permits it), let’s stop and close eyes to recover it
- The first times we will have a lot of difficulties but periodic training will teach our brain to better distinguish objects in the dark and to adapt our pupils faster
- Knowing how to effectively manage night vision is not a skill reserved only for the ancient ninjas, it can also be extremely useful in everyday life (when we drive the car in the evening, when we remain without electricity, etc.)
- All this is not enough to achieve a good level of perceptive night quality; in 6 Dragons Kung Fu, we compensate for the natural limits of our body combining the senses (concentration) with past experience (preparation) and intellect (discipline)
- Night vision must be accompanied by all the other perceptive skills of our school (read for example The overall view: see everything, do not look at anything)
In the next articles of this series, we will see more advanced ways to see in the dark and how to train us (read Advanced training: gradually learn to fight in the dark).
- The most important skill in combat – Why spatial intelligence is better than sight
- Constant attention: what is and how it works – How to reach an alert level similar to the animal’s one
Reply in the comments and share your experience:
- Can you move safely during the night?