Is a dog colour blind?

Dogs are not colour blind. The world in a dog’s eyes is not all black and white, because of the special structure of the dog’s retina, so usually dogs are not able to recognize long wavelength light waves, so they can see the colours black, white, grey, blue, yellow, but also green, red, orange, but because the dog has a weakness of colour, so when the dog sees green in his eyes is grey-white; when the dog sees When the dog sees red it is black or brown in his eyes; when the dog sees orange it is a yellowish colour in his eyes.