ABSTRACT
For a complete understanding of ngermark detection techniques and their application, a good knowledge of chemical and physical phenomena (including a study of light and its interaction with matter) is required. The aim of this chapter is to give some general background theory that will assist the reader in comprehending the development methods described in this book. In addition to basic chemistry and light theory, the chapter also includes a discussion on forensic light sources (FLSs), general photography, and digital image enhancement. An understanding of these basic concepts can assist the examiner in achieving improved contrast and increased overall sensitivity with respect to the detection and recording of ngermarks.
