An apparatus for safeguarding a machine having a machine part performing a working movement, has a light source, a camera unit and a control unit. The light source and camera unit are attached to the machine part so as to concurrently move together with the machine part. The camera unit has an objective body with an optical lens element, an electronic image sensor arranged on a component support, an aperture stop, and a coupling part having a one-piece body by means of which the objective body and the component support are joined in a defined relative position to one another. The one-piece body fixedly rests on the component support thereby holding the aperture stop at a defined position relative to the electronic image sensor without individual adjustment. The control unit is designed to stop the working movement of the machine part depending on a signal produced by the camera unit.