Lighting for Final Piece

I've had a word with Oran about how to light up my pieces from behind. I want the pieces to be illuminated to display the work more clearly. I don't want the light to be too over powering of the image as if the light does become over powering it will make the image look washed out. I thought about having a low wattage spot light behind each panel to illuminate the image. I feel that these will be best, but I will have to play around with the wattage to make sure that the light is not too over powering for the piece or the space.