1. A device for radiometrically gauging the surface of a measurement object (O) that includes effect pigments or flakes embedded in a substrate material, comprising: a. at least one measurement array ( 100 ; 200 ; 300 ; 400 ) featuring an illumination array ( 110 ; 210 ; 410 ) and a pick-up array ( 120 ; 220 ; 420 ); and b. a processor (P) for controlling the illumination array ( 110 ; 210 ; 410 ) and the pick-up array ( 120 ; 220 ; 420 ) and for processing measurement signals produced by the pick-up array ( 120 ; 220 ; 420 ) and for providing processed image data, wherein the illumination array ( 110 ; 210 ; 410 ) comprises at least one light source ( 111 ) and is embodied to expose a region of the measurement object (O) to illumination light at an illumination angle (θ i ) and an illumination aperture angle (α i ), and wherein the pick-up array ( 120 ; 220 ; 420 ) comprises a photoelectric image sensor ( 122 ) and is embodied to capture measurement light, reflected by the measurement object (O), at a pick-up angle (θ v ) and a pick-up aperture angle (α v ) and to direct it onto the image sensor ( 122 ), and wherein the illumination array ( 110 ; 210 ; 410 ) is embodied to produce illumination light in multiple spectral ranges and/or the pick-up array ( 120 ; 220 ; 420 ) is embodied to split captured measurement light into multiple spectral ranges, such that the image sensor ( 122 ) produces multispectral image data, characterised in that the illumination aperture angle (α i ) of the illumination array ( 110 ) and/or the pick-up aperture angle (α v ) of the pick-up array ( 120 ) is/are greater than the angular variation caused by the material dispersion over the spectral measurement range of the light reflected by an effect pigment or flake embedded in the substrate material.