1. A system for estimating the specular roughness of points on a surface of an object comprising: a lighting system configured to illuminate the surface of the object at different times with different illumination patterns, each illumination pattern illuminating the surface from a plurality of different directions and forming an intensity gradient having an order of no more than two; an image capture system configured to capture an image of the surface of the object when illuminated by each of the different illumination patterns at each of the different times; and a computer processing system configured to compute the specular roughness of each point on the surface of the object based on the images captured by the image capture system.