The transformation of medical imaging into a digital medium has been ongoing for many years, substantially affecting radiography in particular. Many traditional concepts of film-screen imaging no longer apply. This has required a change in perspective about the nature of radiographic imaging, from a photo to an electronic data set. These data sets are truly just that- collections of signal data processed by computers into a coherent image. Exposure technique selection is as important as ever, as it directly affects the characteristics of these data sets. In this presentation, we will take a closer look at these digital data sets as they apply to radiographic image production and assessment. The use of quantifiable, numerical values is an effective method for assessing digital image quality. In particular, we will discuss how image underexposure and overexposure affect the electronic data and final image display.