Vision begins with sensation. Light begins a process of transformation as it enters the eye. The cornea focuses the light. The pupil is controlled is by the muscles of the iris to optimize the light, enough for vision without overexposure or damage. The cornea and lens work together to adjust the focal length of the image being formed on the retina at the back of the eye. Photoreceptor cells called cones and rods give an image color and shadow. In the short time it take for an image to form on the retina it has been transformed.
From the retina the image is carried through the optic nerve to the brain for more processing. Perception is the brain’s interpretation of what we sense. For example, the brain attempts to organize sensory information into groups. If multiple dots are seen close together they are grouped into a single bundle for quick processing.
After visual and perceptual processes, the brain encodes information into memories. Short-term memories are translated into long-term memory in the hippocampus. Visual and auditory and other sensory information are combined into a single episodes of memory. The smell of the forest evokes a visual memory of a glade. The memory is personalized.
The eye operates like a camera. It is better in some ways. The lens in the human eye can focus quicker than a camera. But it still operates like a camera, producing a reduced image compared to the original. The retina is like film. Accuracy varies with lighting and resolution depends on the film format or number of pixels. The brain is more efficient than a camera at a price. The brain selectively stores data that it considers important, leaving the rest to be filled in by inference. Any image in the brain is a limited and static capture at a point in time. It is a binding, a copy with error. To a degree, every memory is wrong, an illusion, a lie. Truth is not in the brain — it is out there in the world.