An automatic milking installation controlled by a system including: a graphical user interface enabling user interaction with the automatic milking installation via at least one display view, an imaging unit recording image data representing at least one portion of a dairy animal, the imaging unit having a transparent cover surface configured to protect an optics section of the imaging unit and through which transparent cover surface the image data are recorded, and a control unit receiving the recorded image data, and based thereon, producing a control signal for controlling functions of the automatic milking installation. The control unit further processes the recorded image data to determine a parameter indicating an amount of dirt on the transparent cover surface, and generates graphics data for presentation to the user via the graphical user interface, which includes at least one graphical element reflecting the amount of dirt on the transparent cover surface.
