Abstract: A method for establishing light reflection properties of a specific surface, by measuring, for a plurality of comparison surfaces, the r-tables in accordance with CIE standard recommendations, measuring, for the same plurality of comparison surfaces, a light reflection parameter for selected angles (?) of incident light and angles (90°??) and (?) of reflected light, using a ‘portable’ measuring apparatus, measuring in situ, on multiple measuring points of said specific surface, said parameter for said angles (?), (?) and (?), using said ‘portable’ apparatus, comparing the angular distribution of said parameter for the specific surface with that for said comparison surfaces, to select the comparison surface showing the best distribution fit, optionally taking into account a rescaling factor on luminance coefficient Q0, and assigning to said specific surface the ‘r-table’ corresponding to said selected comparison surface, with said optional rescaling factor.

Abstract: A method for establishing light reflection properties of a specific surface, by measuring, for a plurality of comparison surfaces, the r-tables in accordance with CIE standard recommendations, measuring, for the same plurality of comparison surfaces, a light reflection parameter for selected angles (?) of incident light and angles (90°—?) and (?) of reflected light, using a ‘portable’ measuring apparatus, measuring in situ, on multiple measuring points of said specific surface, said parameter for said angles (?), (?) and (?), using said ‘portable’ apparatus, comparing the angular distribution of said parameter for the specific surface with that for said comparison surfaces, to select the comparison surface showing the best distribution fit, optionally taking into account a resealing factor on luminance coefficient Q0, and assigning to said specific surface the ‘r-table’ corresponding to said selected comparison surface, with said optional resealing factor.