Surely more than once you have wondered if your dog or cat can watch television, if they are only able to see in black or white, why they don't react to your presence when you're far away or why they can't find the red ball in the middle of the garden that, for you, is obvious. This all has to do with what the features and functions of your vision are, as opposed to ours. This is how they see the world.
The vision of dogs and cats is less sharp than ours. This is because they have less visual acuity, that is, less ability to distinguish details than humans, and cats see even less detail than dogs. If you have ever appeared in a place where your dog did not expect to find you and you were far from him, it is understandable that your dog did not recognize you. In fact, for a dog to see the same as a person with good vision, the dog would need to be three times as close to the object. And in the case of a cat, much closer.
On the other hand, if they are too close to an object they don't see it well either. When children can focus on things as close as 7 cm from their eyes, cats need a minimum of 25-36 cm and dogs between 33 and 50 cm to focus on objects located at different distances. So, if we want them to "see" something, it is better not to place it right in front of their snouts, since in this way they will explore it more with smell and touch, instead of with sight.
Indeed, they can be, and when they are, their visual acuity is further reduced. This alteration is documented in both cats and dogs. What's more, there are some dog breeds that can suffer from it more frequently than others. So how do you know if a dog or cat needs glasses? Taking him to the vet to assess if there is a defect in his vision.
It depends on the television and the number of images per second that it emits. When a certain emission frequency is exceeded, the eyes come to merge the images and see a single moving image, while below this frequency, the eyes perceive flickering images. The frequency required to merge images is estimated to be 55 Hz in cats and 80 Hz in dogs.
Televisions are designed for our eyes to see real images without flickering, but the most modern televisions have an image refresh rate that is enough even for dogs and cats to see television well. And, then, what TV programs attract your attention? For dogs, images of other dogs and people, while for cats, images of moving prey.
One of the most widespread beliefs is that dogs and cats see in black and white. They can actually see colors, but not as much as humans. They live surrounded by two colors: yellow-green and blue, although we cannot know if they perceive them as we do. What you see as red is seen by your dog or cat as a dark yellow.
Something similar happens with green, which is why they cannot easily differentiate a red object from a green one. Therefore, if you throw them a red ball on a green background, such as the grass, if they haven't seen it moving for them to find it, it will surely require the use of other senses.
Yes, but never in conditions of total blackness, since there has to be a minimum illumination so that they can see something. Of course, dogs, and even more so, cats can see much better than people in low light conditions. Cats need almost six times less light than we do to see anything, while dogs fall somewhere in the middle, but possibly closer to feline than human ability.
The visual field is all the space that we can perceive while our eyes are looking forward. Ours is 180º, while in cats it can measure up to 200º and, in the case of dogs, it depends on the breed. For a dog with intermediate characteristics (that is, with a snout that is neither flat nor elongated) the visual field measures about 240º. This allows dogs to have much more developed peripheral vision. Its side vision is not very precise, but enough so that if there is something interesting to the dog, like something moving, it motivates it to turn its head and look at it.
When turning the head, the moving object ends up right in the middle of the area of the visual field where the images perceived by each eye overlap. This area is key to perceiving three-dimensionality and calculating how far away the objects in front of us are placed. You should know that this zone measures approximately 90º in cats and 60º in dogs (although in the latter there may be variations due to the shape of the muzzle and the position of the eyes), while in people it measures 140º.
What our cats and dogs see is very different from what we see. Their way of perceiving the world is unique, being a reflection of their origins, of their past as hunters, but also the result of their adaptation to the environment. Ahead of the vision of details and colors, sensitivity to movement has passed, the ability to see in low light and to calculate distances well. Like good pet parents, knowing how they see everything around them will make us understand them better.
*Source used to make this article:
https://www.ultima-affinity.com/es/es/all/como-ven-los-perros-y-los-gatos/
