1. A method for measuring the gloss of grains, the method comprising: emitting a light beam to the surface of the grains by means of a light emitting device; aligning a light sensing device in a sensing position in relation to the light emitting device sensing the light beam of the light emitting device reflected by the surface of the grains in a direction of the light sensing device; capturing a photometric image of the surface of the grains by means of the light sensing device sensing the reflected light beam; assigning an intensity value to a plurality of image elements of the captured photometric image, wherein the photometric image is composed of the plurality of image elements; quantifying the reflected light beam in predefined ranges of intensities by means of a processing unit; cumulating the number of image elements having an intensity value within each of the predefined ranges; assigning a density value to each of the predefined ranges, each density value corresponding to a cumulated number of image elements within one of the predefined range; calculating a spread value for the density values of the predefined ranges by means of the processing unit, wherein the spread value is calculated by measuring a deviation of the density values of the predefined ranges; and assigning a quality surface measuring parameter to the captured photometric image, wherein the surface measuring parameter is a measure the spread value.