The retina is the light sensitive portion of the eye. This structure is located in the back of the inside of the eyeball. Cones provide color perception and detailed sight, while rods detect motion and vision in dim light. Dogs have rod-dominated retinas that allow them to see well in the dark. Along with superior night vision, dogs have better motion visibility than humans have.
Dogs see like a color-blind human.
Dogs' retinas can distinguish two colors. These colors are blue-violet and yellow. Dogs can also differentiate between shades of gray. Dogs are unable to recognize green, yellow, orange, and red. This, along with the flow and noise of traffic, tell the dog that it is the right time to cross the street.