Sketched background oil portrait

In 1828, Sir Thomas Lawrence did this portrait of William Wilberforce. It is a primary sketch on a prepared background using a graphite piece and then adding oil paint to the face area. Perhaps the balance was left to his students who were also called 'drapery artists' to finish the details. Sir Joshua Reynolds did this by painting just the faces and his many students finished the balance. In this manner Reynolds could do as many as 6 portraits in a 10 AM until 4 PM workday