A camera obscura’s pinhole is unable to zoom in on any particular object
in a scene. This level of control requires a lens to be placed
at the pinhole of the camera obscura.
Johannes Kepler (1571-1630) tested the use of a lens in a camera obscura.
The lens collects and focuses light much better than a pinhole.
The resulting image projected onto the back of a lens-based camera obscura
is much brighter. Kepler’s interest in lenses and optics led to
great contributions to our understanding of how the human eye works.