1. A method for determining characterization data for use in a printing process, the method comprising the following steps: initially printing at least one test element, having a number of colored areas, on a printing material; assigning tonal values of at least one printing ink to the colored areas; measuring the colored areas of the at least one test element with a spectral measuring instrument to determine measured results; storing the measured results as actual spectral data; determining a first tonal value gain for the assigned tonal values of the colored areas of a first subset of the actual data; determining a first tonal value gain curve or tonal value curve by interpolation from the first tonal value gains of the assigned tonal values; determining at least one parameter of a model for calculating color values of the printing process using a second subset of the actual data; determining at least one of a second tonal value curve or tonal value gain curve for the printing process from the model; comparing the first and second tonal value curves or tonal value gain curves with one another; and determining a correction curve for adapting the tonal values of the model from the first tonal value curve or tonal value gain curve, and calculating characterization data of the printing process using the model while taking the correction curve into account.