Portrait photography is a popular commercial industry all over the world. Many people enjoy having professionally made family portraits to hang in their homes, or special portraits to commemorate certain events, such as graduations or weddings. Since the dawn of photography, people have made portraits. The popularity of the daguerreotype in the middle of the 19th century was due in large part to the demand for inexpensive portraiture. Studios sprang up in cities around the world, some cranking out more than 500 plates a day. The style of these early works reflected the technical challenges associated with 30-second exposure times and the painterly aesthetic of the time. Subjects were generally seated against plain backgrounds and lit with the soft light of an overhead window and whatever else could be reflected with mirrors.