Night Vision
What is night vision?
Night vision is the eye's ability to see in low-light conditions, which relies primarily on the rods rather than the cones. Once fully adapted to darkness, the rods become roughly 10,000 times more sensitive to light than the cones, but they adapt slowly—taking time to adjust, like walking from bright sunlight into a dark movie theater. Because the rods are concentrated away from the fovea (the center of vision), they also handle much of your peripheral vision at night. Think of it as: at night, you see best by looking slightly to the side of an object rather than straight at it.
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