After the definition of the optical model (i.e. materials, the layer stacks and the spectra including the import of the experimental data) the parameters that are going to be varied in order to optimize the agreement of model and measured data must be selected from all model parameters. These chosen parameters are called the fit parameters. The agreement of model and measured data is given by the so-called fit deviation. Based on the fit deviation you can classify the agreement between model and experiment. This rating is described below.

Fit parameters are managed in the list of fit parameters (opened by a right-click of the corresponding treeview item).

In order to inspect the influence of a parameter on the computed spectra the actions called Parameter variation and Parameter fluctuation are very useful. These are described in the section about the SCOUT workbook.