Hi Warren. You might try: In a precomp the same size as your final images, make a solid (say 200x200 for the sake of explanation), add the Ramp Effect, keyframe Start Color and End Color both black, move ahead a few frames and set Start Color to white, then move ahead about double the number of frames and set the End Color to white. Duplicate the solid and position them into a solid mass filling the precomp. Then offset/drag the layers so they ramp from black to white in the order you want. Use this as a Track Matte for your image(s).