Although the book implies that this is specifically about Alice Liddell, it is really only about the photograph of her as the beggar girl that Dodgson had taken of her, and of Dodgson's photography in general, in addition to a brief history of photography. Unfortunately,however, that is the only photo in the book---especially since it is constantly being compared to the other picture that had been taken of Alice that day in which she was in typical (and formal) VictoriaN attire. It is also later mentioned that Alice had posed for a similar picture years later for Julia Margaret Cameron, but again it is not shown.
I think that the author over rates her book in the suggestions for further reading section by stating that it: "adds minutely to the patina of knowledge".
Very little new information is contained in it at all.