Both of them. Each of them experiences reality in a different way, and each of them only experiences a part of reality.
We know through our own experience of using dogs to follow scents that their sense of smell is correlated with external reality. We have a sense of smell but not nearly as refined as a dog's, so, we are not able to make the distinctions that a dog can.
A dog's sense of vision works quite well for navigating through the outside world - they rarely bump into things, can accurately see both predator and prey. Their vision isn't as refined as ours, so, I'm sure that they can't see some of the details that we see.
Our perceptions are a part of reality, and they usually correlate with the external world well-enough to enable us to navigate through the world successfully. In some forms of mental illness, such as illnesses that cause hallucinations, human perception does not correlate well with the external world. But those perceptions, even hallucinatory ones, do have a correlation with reality. The human brain is part of reality. Understanding why the perceptions of certain people don't correlate with the external world can teach us about ourselves, how we perceive things, and how those perceptions can go wrong.
But, take our perception of color. Do you think that various wavelengths of electromagnetic radiation are actually different colors? Or, do we just perceive it that way? IOW, does our perception of a colorful world actually reflect external reality? I doubt it. But, color is an extremely important part of the human experience; and there is a correlation with the outside world.
The sense of awe that most people feel when they look at the Grand Canyon is also a part of our perception of reality. Presumably, there is some adaptive advantage to this sense, or we would not expect it to be so widespread, seemingly universal across humanity. If we don't know what the adaptive advantage is, that doesn't mean that there isn't one. We can't define external reality; but, we can share our sense of reality with other people. That sharing can lead us to a better understanding of the world we live in.