MILK looks exactly the same as white paint—or at least it does in
computer graphics animations. So animators spend hours doctoring shots to make a
glass of milk look convincing enough that you want to pick it up and take a
sip.
When you shine light into a glass of milk, some photons bounce off the
surface but most continue, bouncing back and forth off the microscopic fat and
protein molecules suspended in the liquid before being reflected. This
“subsurface scattering” gives milk a soft look that makes it easily
distinguishable from a glass of white paint—at least to…
