Wall-mounted cameras record their hand movements on the keyboard, mouse, and any associated documentation, as well as their facial expressions. A voice-activated microphone records any comments they make. All these data are fed into the control room, where evaluators monitor all sources on independent screens. Here the evaluator can control camera angle and zoom, allowing the user complete freedom to move yet ensuring all data of interest are captured. Obviously the lab is a place where users can test software but once captured, the data can be mixed down to emphasize specific points, show highlights, problem areas or specific usability issues.
Evaluators can replay specific parts of the interaction to identify patterns of errors.
Since the data are timestamped, researchers and evaluators can build up a highly detailed picture of the interaction to ensure their interpretations of problems are accurate. Video editing also enables multiple hours of data capture to be synthesized for presentations to design teams or software purchasers.