runback occurs when you leave a
pool of pigment on the paper.
These can creep or run back as
the surrounding area dries and
resembles a small explosion.When
carefully planned they can create
use a granular pigment there is
not as much action to the
explosion as when you use smooth
or non granular pigments
and experimentation will help you
gain a complete understanding of
these techniques so you can use
them with confidence.