I painted/tinted the lightsaber directly on the video frame by frame using a Wacom tablet in Bauhaus Mirage, which is kind of like After Effects, but it has a lot more of the 2D capabilities of Photoshop or Corel Painter (so its like a PS for compositing and animation) - its no longer available for sale, but its successor software is called TVPaint. Hypothetically, though, the process could also be done in PS (except instead of painting on the video file, you'd have to paint on the frames as Tiff or Targa images).