Here are 9 tiny toy cars lined up along a yard stick for an experiment in
something called "Focus Stacking".


In closeup photography the lens can focus on the near point of the subject
or the far point of the subject, but not on both at the same time. The top
two photos demonstrate that limitation. Getting around that limitation so
that everything is in focus is a physical impossibility due to the laws of
optics.


However, software gives us a way to do digitally what we cannot do in the
real world due to that physical limitation. The bottom picture is actually
made up of 17 separate photographs, each one focused a little further back
on the subject. They are combined digitally with a program called Helicon
Focus into one composite image with all parts in focus.