Abstract: A method for determining the amount of a specific analyte by photometric assays, wherein the specific analyte in a sample reacts with an analyte specific reaction partner in a reaction mixture. At least two calibration curves are generated, the first calibration curve recorded at a first wavelength is optimized for low concentrations of the specific analyte thereby maximizing the lower detection limit and, the second calibration curve recorded at a second wavelength is optimized for high concentrations of the specific analyte thereby maximizing the upper detection limit. The optimized lower detection limit and the optimized upper detection limit results in an extended dynamic range.