In some configurations information about several specimen properties is gathered per pixel, usually by the use of multiple detectors. In SEM, the attributes of topography and material contrast can be obtained by a pair of backscattered electron detectors and such attributes can be superimposed in a single colour image by assigning a different primary colour to each attribute. Similarly, a combination of backscattered and secondary electron signals can be assigned to different colours and superimposed on a single colour micrograph displaying simultaneously the properties of the specimen.