The movie and broadcast industries are gaining experience with high-dynamic-range (HDR) video technologies and are starting to produce HDR content at scale. This is accompanied by a learning process, particularly involving questions regarding the use of the extra dynamic range afforded by these technologies. To create further insight into the aspects of HDR content, in this paper, a variety of different types of content is analyzed. Manual annotation processes are used to determine the range of luminance values that, for example, diffuse white objects or white overlay graphics objects have in this content. We found that, for each type of object analyzed, the mean luminance value is reasonably constant across different types of content, but the spread of luminance values is remarkably large and strongly content dependent. Our results may form a basis for understanding HDR content and contribute toward forming opinions on defining reference levels in reports and standards, including International Telecommunications Union - Radiocommunication Rec. BT.2408.