Dogs are not color blind
We humans have three types of optic cone cells while dogs only have two.
This means that a human can recognize a combination of red, blue and green colors, while a puppy can only recognize a combination of yellow and blue colors.
So dogs are not color blind, they are just color blind, they don't only see black, white and gray
Dogs are nearsighted
The ciliary muscle of the dog's eyes is weak, and the focus cannot be freely adjusted. Adjustment ability is only 1/5 to 1/3 of the human, for stationary targets, the dog's range of vision is relatively limited, the farthest you can only see about 50 meters.
But for dynamic targets, the dog's field of vision capture ability can reach 1000 meters, for the movement of objects is very sensitive, and its dynamic visual acuity is more than twice as much as that of a human.
Ultra-wide-angle field of view
Human eyes are on the front, the angle of vision is at 180 degrees.
The dog's eyes are more on both sides, the dog's pupil is bigger than human's, the retinal cell content is more, according to the different dog breeds, the angle of vision is 250~290 degrees.
Dogs have good night vision
Dogs have much better night vision than humans.
Because dogs have 2-3 times more visual cells in the retina than humans, the eye's ability to focus and sense light is 6 times greater than that of humans.
Dogs are able to see clearly around them at night in especially low light conditions.
