DARK ADAPTATION

In ocular physiology, adaptation is the ability of the eye to adjust to various levels of darkness and light.The human eye can function from very dark to very bright levels of light - its sensing capabilities reach across nine orders of magnitude. This means that the brightest and the darkest light signal that the eye can sense are a factor of roughly one thousand million apart. However, in any given moment of time, the eye can only sense a contrast ratio of one thousand. What enables the wider reach is that the eye adapts its definition of what is black. The light level that is interpreted as "black" can be shifted across six orders of magnitude - a factor of one million.
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Dark adaptation n. The adjustment of the eye under reduced illumination, in which sensitivity to light is greatly increased. [more]Dark adaptation - Community and Resources

Noun
1. the process of adjusting the eyes to low levels of illumination; cones adapt first; rods continue to adapt for up to four hours
(hypernym) adaptation

B: (Biologi) adaptasi gelap
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Eng: dark adaptation
Urdu: تیرہ خوگری۔ وہ عمل جس کے ذریعے آنکھ کم روشنی سے مطابقت پیدا کرتی ہے۔