Many of today’s cars are coated with paint that exhibits a metallic or glittery shine. The exact sparkle and color you see is determined by the distribution and characteristics of tiny metal flakes used in the paint. A new approach based on the medical imaging technique optical coherence tomography (OCT) provides the car industry with a practical way to automatically analyze these metal flakes, which until now have been difficult to image, in order to improve the efficiency of the automotive finishing process.