A device for radiometrically gauging the surface of a measurement object (O) includes: at least one measurement array featuring an illumination array and a pick-up array; and a processor (P) for controlling the illumination array and the pick-up array and for processing measurement signals produced by the pick-up array and for providing processed image data. The illumination array exposes a region of the measurement object (O) to illumination light at an illumination angle (θi) and an illumination aperture angle (αi), and the pick-up array captures measurement light, reflected by the measurement object (O), at a pick-up angle (θv) and a pick-up aperture angle (αv) and guides it onto an image sensor exhibiting a pixel structure. The measurement object (O) is gauged multispectrally in multiple wavelength ranges, wherein the image sensor produces multispectral image data. Angular and spatial conditions are indicated which optimise the measurement device (MD) with regard to characterising sparkles.