A control unit for an automatic device for preparing a beverage is provided with an input which enables the user to choose from a plurality of formulations a formulation for the beverage to be prepared. The control unit is provided with an operating unit for controlling a preparation unit of the automatic device. The input comprises an image input for visually observing the user and for generating image signals which are representative of the visual observation. The operating unit is arranged for generating control signals for the preparation unit of the automatic device as a reaction to the image signals.
