How did John Constable use oil sketches to prepare finished paintings?

John Constable utilized oil sketches as a fundamental part of his artistic process, employing them in two primary ways: as discrete studies of nature or as preparatory work for his larger easel paintings.1

When preparing his major exhibition pieces, Constable followed a rigorous academic practice. He would create various oil and pencil sketches to explore his subject matter. Before executing the final version of a large-scale work, he would essay the composition onto a full-scale canvas based on these preliminary studies. This methodical approach allowed him to labor over his large, detailed paintings, ensuring they met the standards of grand academic art of the period.2

While other artists of his time also produced sketches, Constable was unique in the extent and intensity with which he used the medium. His sketches allowed him to capture naturalistic effects and fleeting meteorological phenomena, which he then synthesized into his finished compositions.32