From light to signal

The visual pathway.

The retina

Rods handle dim light without colour, cones handle colour in three types. The signal is processed in the retina before it leaves the eye, then travels to the visual cortex at the back of the brain.

The blind spot where the optic nerve exits is filled in by the brain.
Sharp vision covers a tiny central area; the rest is much lower resolution.

Eye movements

Eyes jump several times a second, and vision is suppressed during the jump. The stable scene you experience is stitched from those snapshots.