A couple of days ago I mentioned the difficulty of capturing a scene that was mostly white, and the need to over expose it to trick the light meter. There is a similar difficult with capturing a scene that is mostly black. The light meter will lighten up the scene to achieve an average value of grayness, because that's what works for most scenes. When photographing a mostly black scene, one must underexpose so that when the light meter tries to "gray out" the scene, it achieves black. This image is two full stops underexposed. A black cast iron kettle with a black backdrop.