The amount of lateral charge migration (LCM) on a photoreceptor is quantified by measuring the average potential of a latent image formed on the photoreceptor surface. The surface is first uniformly charged, then exposed a first time to an image. After a waiting period during which LCM may occur, the surface is exposed a second time to the image. After another waiting period, the average potential is measured. The amount of LCM may be quantified by varying the waiting periods.