Low light levels in museums is really a problem. Currently in Omaha at the Joslyn Museum is a show of about 100 Picasso prints, linocuts, aquatints, lithographs etc. the light is so low that it is virtually imposible to really study the prints, expecially the smaller pieces.
I am almost to the point where I would rather see a copy of each work under good light rather then the original under low light. you probably would have a better impression of the intent of the artist.