Pedagogy and the Visual Image

Dilemma: I don't think our problem is using visual sources in history. In fact, we are always using pictures, photographs and the moving image in our teaching. In practically every theme, there is something that can be described as visual but when I add up what we do, there does seem to be an issue of what we use and the way we use them. I am sure there is a greater variety of visual sources than those we use and I am even more convinced that we can do rather more than use the image as stimulus or to aid simple comprehension. What are we doing wrong?