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If you want your eyes to receive 32000~100000lux, you need to stare at the sun in a sunny day.If you stare at the ground in a sun-exposure area, your eyes receives much less than 32000 lux. If you stare at a shedded ground in a sunny day, your eyes receive slight less than 10000lux. human eyes could not tolerate 32000lux more than 5 secounds


Because in the retina of human eyes there are light detector cells of two kinds: rods and cones. Cones "see" colors but are not very good with low brightness. Rods don't detect colors but are better than rods in low brightness situations. Thus at night cones don't function (they are for bright light) and we see only with rods which don't differentiate ...


With my understanding, any color except black will reflect light, and a black color will absorb light without reflecting back out. So, at night, there won't be enough light to shine on anything to have a reflection. Then, your eyes won't see anything

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