Horses are not color blind, they have two-color, or dichromatic vision.
In other words, horses naturally see the blue and green colors of the spectrum and the color variations based upon them, but cannot distinguish red.
Can horses see white?
Many people think that animals, including horses, are colorblind and only see in shades of gray. Horses do see color, but they may not see it as vividly as we do. This is because they can only see two of the three visible wavelengths in the light spectrum, which is somewhat similar to the way colorblind humans see.
How do horses see humans?
A horse’s eyes are set far apart, so his ability to see depth is limited. From most angles, horses cannot get a left-eye and right-eye view of the same object in one glance. People can see an outstretched finger with both eyes simultaneously.
What Colours can horses not see?
A horse’s vision is similar to a person who is red-green color blind. Horses can only see blues and yellows. However, unlike a human, a horse can probably not see any intermediate hues. The four photos below come from the journal article.
Can horses see purple?
Neither could they see the circle when it was made of red-purple or blue-purple dots on a dotted grey background. It is most likely that horses see the world in a similar way to humans with red-green colour deficiencies. Red, orange, yellow and green probably all appear the same.