Technical publications sometimes include scanning electron images to characterize a microstructure, when the relevant structure could have very easily been illustrated using a simple light micrograph. When should one use a light generated image? What are the advantages/disadvantages of an electron generated image, particularly; one generated using a scanning electron microscope (SEM)? While there is some overlap in the capabilities of these imaging systems; in general, they are complementary tools, each with their own uses. Standards under the jurisdiction of ASTM Committee E4 on Metallography offer guidance to both new and experienced users of both investigative techniques.