A method of modeling an edge profile for a layer of material is provided. The layer of material can include a resist and/or an etch. In this method, multiple models can be generated, wherein at least two models correspond to different elevations on the wafer. Each model includes an optical model, which has been calibrated using test measurements at the respective elevations. In this manner, an accurate edge profile can be quickly created using the multiple models. Based on the edge profile, layout, mask, and/or process conditions can be modified to improve wafer printing.