Usually a study is not used for an official portrait in a public place.
However, this page is included under both personal
and public portraits since some of the studies may be preliminary
to a final public portrait.
A "study" in portraiture can occur under various circumstances.
Generally they are fairly quick paintings with loose brushstrokes.
Sometimes they are done during a workshop, either as a student or
teacher. Other times they are preliminary to a final
painting to work out color and composition. Most artists will sell
their studies when someone is interested. And,
some artists offer a "study" as an alternative to a more
finished portrait with tighter strokes.
The degree of finished detail can vary from one artist to another.