The way how our vision responds to lighting conditions heavily relies on the amount of light that our eyes receive. Depending on that, our rods and cons are activated almost exclusively.
The three modes of vision are considered:
- Photopic vision: vision, when our eyes receive enough light (apx. more than 10 cd/m2). It is normal day vision, where the colors are perceived best, and sharpness is at highest levels. This vision is supported by cones of our retina.
- Scotopic vision: night vision, when there is almost no light (less than 10-3 cd/m2). This vision is supported by rods, so it is not differentiating colors and not sensitive to red part of photopic spectrum.
- Mesopic vision: combination of both photopic and scotopic vision under twilight conditions, so both cones and rods are activated.