CCI perennially needs to justify museum light levels being recommended to clients, but existing evidence is not persuasive. Therefore, samples of old, undamaged colors in various media were damaged with measured light exposures (Xenon arc with and without ultraviolet filters). Photographic transparencies of all the results are now an effective part of CCI's training and information resources. To reach a wider audience, a wall poster was produced which incorporates salient description with a few dramatic examples. See also AATA 21-1380 for entire proceedings.