1. A viewing system, comprising: a detector of electromagnetic radiation mounted on a frame; one or more controllable electromagnetic radiation guides mounted on the frame to guide electromagnetic radiation from a target area to the detector; and a control system connected to receive signals from the detector, and configured to: identify a dental mirror, disposed within a field of view of the detector in use, identify a feature of interest that is within the field of view and that is visible in the dental mirror, select for detection and tracking by the detector the feature of interest that is visible in the dental mirror by directing electromagnetic radiation to the detector using the dental mirror and the controllable electromagnetic radiation guides, track the dental mirror, and continue to track the feature of interest independently of the dental mirror, the feature of interest being distinct from the dental mirror; wherein the detection and tracking Includes manipulating the controllable electromagnetic radiation guides to view the feature of interest from a different field of view or optimal angle of view; displaying an image on a display in which the feature of interest is visible.