A method for detecting the surface allocation of a coating on a surface of a strip-shaped test piece, with the steps of: moving the strip-shaped test piece in a feed direction, detecting a parameter of the surface allocation of the coating line by line using a first measuring procedure which comprises the steps of: illuminating the surface of the test piece with electromagnetic radiation at a plurality of locations in a line extending substantially perpendicular to the feed direction, measuring, using a detector, a respective intensity of electromagnetic radiation reflected, backscattered or emitted from the coating at the locations in the line, and determining a parameter for the surface allocation of the coating at the locations in the line from the intensity detected by the detector, carrying out a calibration measurement at a location of the line with a second measuring procedure which is different from the first measuring procedure, wherein the second measuring procedure is configured in a manner such that it detects a parameter for a surface allocation of the coating at the location in the line, and calibrating the parameter for the surface allocation of the coating determined by means of the first measuring procedure on the basis of the parameter for the surface allocation of the coating detected by the second measuring procedure, wherein the calibration measurement is carried out using the second measuring procedure at precisely one or at a plurality of locations in the line, wherein the number of locations at which the calibration measurement is carried out is smaller than the number of locations at which the measurement using the first measuring procedure is carried out. moving the strip-shaped test piece in a feed direction, detecting a parameter of the surface allocation of the coating line by line using a first measuring procedure which comprises the steps of: illuminating the surface of the test piece with electromagnetic radiation at a plurality of locations in a line extending substantially perpendicular to the feed direction, measuring, using a detector, a respective intensity of electromagnetic radiation reflected, backscattered or emitted from the coating at the locations in the line, and determining a parameter for the surface allocation of the coating at the locations in the line from the intensity detected by the detector, illuminating the surface of the test piece with electromagnetic radiation at a plurality of locations in a line extending substantially perpendicular to the feed direction, measuring, using a detector, a respective intensity of electromagnetic radiation reflected, backscattered or emitted from the coating at the locations in the line, and determining a parameter for the surface allocation of the coating at the locations in the line from the intensity detected by the detector, carrying out a calibration measurement at a location of the line with a second measuring procedure which is different from the first measuring procedure, wherein the second measuring procedure is configured in a manner such that it detects a parameter for a surface allocation of the coating at the location in the line, and calibrating the parameter for the surface allocation of the coating determined by means of the first measuring procedure on the basis of the parameter for the surface allocation of the coating detected by the second measuring procedure, wherein the calibration measurement is carried out using the second measuring procedure at precisely one or at a plurality of locations in the line, wherein the number of locations at which the calibration measurement is carried out is smaller than the number of locations at which the measurement using the first measuring procedure is carried out.