1. A method for digitally reconstructing the surface of an object, comprising: receiving image data including pixel values from one or more two-dimensional optical images of the object; estimating surface gradient information for each pixel location from the image data, the surface gradient information representing the approximate slopes at locations on the surface of the object corresponding to the pixel locations; and determining surface height information defining the shape of the surface of the object in greater than two dimensions using said surface gradient information and noise information representing the noise distribution in the one or more optical images.