Dog Vision
While all dogs can detect object in motion, visual acuity and visual fields vary from breed to breed andf from dog to dog. Sight Hounds, for example, see better than dogs that hunt and sense primarily by scent. Sight Hounds can also see nearly three-quarters of the way around their heads. The Visual field of Scent Hounds, on the other hand, is limited to slightly more than halfway around their heads. This field is quite broad, however, when compared to humans, who only see within one-third of the range around tier heads. Dogs also possess stereoscopic ability, or the physical set-up to see objects in three dimensions, due to the forward position of their eyes. This skill is limited, however, to a far narrower range than that of humans, Most dogs have difficulty focusing on objects at close range or distinguishing how far an object is from their vantage point. They can see in color, but have a form of green color blindness, which alters their perception of blues, greens and reds. Blues and greens appear white, while reds appear yellow. Overall, dogs can still distinguish many colors, but perceive them differently and in a more limited way than humans do.