The human eyes vision over the several light intensity ranges, which are usually based on the rods and cones. The rods and cones constitute the unique visual pigments for absorbing different light wavelength and activation threshold units.
The rods constitute the high sensitive ability to respond to the dim light and is best suited for the night vision. This further helps to absorb the visible light wavelength to form the gray colored toning image vision.
The cones constitute the low sensitive ability to activate the bright light pigments for viewing vivid colors. Due to this collision, the rods and cones are densely packed over the fovea of the eyes and make the night vision more fuzzy and indistinct.