This document discusses a photometric stereovision technique to localize free 3D surfaces using multiple images. It presents a photometric model linking image intensity to surface relief and reflectance properties. This model results in a system of equations with the relief variations and reflectance as unknowns. Solving the system requires 3 images under different lighting conditions. The document applies this technique to extract the 3D relief of a corrugated plastic surface from images, demonstrating the feasibility of measuring free surfaces with the photometric stereovision approach. Accuracy of the measured surface shape is evaluated.