The present invention relates to an apparatus for analyzing an element of a photolithography process, said apparatus comprising: (a) a first measuring apparatus for recording first data of the element; and (b) means for transforming the first data into second, non-measured data, which correspond to measurement data of a measurement of the element with a second measuring apparatus; (c) wherein the means comprise a transformation model, which has been trained using a multiplicity of first data used for training purposes and second data corresponding therewith, which are linked to the second measuring apparatus.