Disclosed is an apparatus for determining surface properties, comprising at least a first radiation device which emits radiation onto a surface to be analysed, at least a first radiation detector device which receives at least part of the radiation emitted by the at least one radiation device and then scattered or reflected by the surface and outputs at least a first measurement signal which is characteristic of the reflected or scattered radiation, and at least a second radiation detector device which receives at least part of the radiation emitted by the at least one radiation device and then scattered or reflected by a surface and outputs at least a second measurement signal which is characteristic of the reflected or scattered radiation. According to the disclosure, the first radiation detector device is offset by a first predefined angle .beta.1 with respect to the direction of the radiation reflected by the surface, and the further radiation detector device is offset by further predefined angle .gamma.1 with respect to the direction of the radiation reflected by the surface, and the ratio between the value of the further predefined angle .gamma.1 and the value of the first predefined angle .beta.1 is at least 1.5:1.