Exposure can get pretty technical, so it’s important to grasp the basic concepts first before we plunge into the world of exposure control for technical and artistic purposes. In the 1890s, Ferdinand Hurter and Vero Driffield invented a way to measure how exposure affected a film negative. There are two ways to think about exposure: overall exposure and balance within the frame. Exposure affects many things: it’s also about whether or not an image will be noisy, it’s about the overall contrast of the image, and it’s about whether or not we will see detail and subtleties in the shadows and in the highlights. The same principles of exposure apply to video; the same ideas of the curve, toe, and shoulder, also apply, although in video the highlights are called the knee and the darkest parts of the scene are simply referred to as shadow areas.