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How To See In The Dark

Spies need to keep their eyes open in order to collect valuable clues and information.  Sometimes, we even need to see in the dark. Maybe it's the middle of the night or inside a very dark room, whatever the case, you can't always to turn lights on when you're a spy. Someone might notice the mysterious chicken in their midst.

So, how does the smart agent manage to see in the dark? Here are some tricks of the trade: 


At the front of each eye ball, you'll find a small hole called the pupil. It will look like a black spot in the middle of your eye. The pupil gets bigger and smaller to let the right amount of light into our eyes. When we are in a bright area, the pupil gets smaller to prevent too much light from entering our eyes. In a dark area, the pupil will naturally get larger to let in more light. If you will be trying to see in a dark area, try closing your eyes for a few moments beforehand, this will help your pupils open fully and will allow your eyes to collect as much light as possible.

Pro tip: When attempting this maneuver, stay away from lights. If you happen to look at a bright light source your pupils will close up again, undoing all of your hard work.

You can also try peering out of the corners of your eyes. Scientists have identified two types of detectors on our retina – rods and cones. Cones detect colours and are more heavily concentrated at the centre of our retina. They need quite a bit of light in order to function properly. Rods detect the difference between light and dark areas (shapes) and are more evenly spread across our whole retina. Rods can also operate at much lower light levels than cones. By looking out of the corners of your eyes, you bring your rods into play which allows you to detect things at lower light levels than the cones at the front of your eyes.


Inventors have created many devices to improve how we see at night. 

  • Infrared cameras detect heat given off by living creatures, certain types of machinery, and other phenomenon. 

  • Active Infrared systems use special goggles that can detect infrared light and an infrared flashlight that puts out light that is invisible without the special goggles. Although, if another spy also has the special goggles they will spot you and your flashlight pretty quickly.

  • Image enhancers can detect very small amounts of visible light and amplify it on a small display screen so that our eyes can see it.


A team of researchers from California created eye drops made from Chlorin e6, a chemical found in some deep sea fish that allows them to navigate in very low light environments. The researchers found that when Chlorin drops were put in their test subject’s eyes, his ability to see in low light conditions improved significantly.

Until next time, here’s fish in your eye!


Did you miss last week's transmission? Read on to learn about "Famous Canadian Spies". Try seeing in the dark with an active infrared camera system in the Top Secret: License to Spy exhibition, on now until September 5.