The Shadow Catcher is a highly enjoyable novel. The frame story uses a device that seems to be coming up in a lot of very recent books: the main character, who tells the story, has the same name as the author, and seems to have many similar characteristics. "Marianne Wiggins" -- the character who might be the author -- begins with some observations about artwork: "Let me tell you about the sketch by Leonardo I saw one afernoon in the Queen's Gallery in London a decade ago, and why I think it haunts me." (p. 1)
The first two chapters could possibly be autobiograpical: the narrator is a writer, trying to sell a script to an unnamed Hollywood personality. She lives in LA and obsesses about traffic and alterate ways to avoid the worst congestion. She knows about celebrities. She has a home and a car. Her book is about Edward Curtis, photographer, who created the common understanding of what it looked like to be an Indian. All the details of her life could be either truth or fiction: it's not a critical matter.
On page 43, the novel turns to "her" book. It starts with the early life of Edward Curtis's wife Clara, daughter of a painter whose works are no longer desired because photography has replaced his skills. We see how she and her younger brother happened to travel out to the territory of Washington to live with his family. As Clara meets Edward Curtis, we meet him. As he develops into a skilled and artful photographer, we see him through her eyes, and we find out how she teaches him what she's learned about painting: the link to the first thoughts of "Marianne Wiggins" and her passion for Renaissance Italian art.
A marvelous aspect of The Shadow Catcher is the constant reference to the works of Curtis, which are reproduced so much that every reader can probably visualize them. In case you don't have the photos in your mind's eye, very small reproductions of the works and of other relevant material appear in the text: I think the use of illustrations in a novel is another 21st century trick that's coming into its own. You can also find very good reproductions online -- as I showed.
Eventually a completely unexpected turn of events in the Frame Story causes an unexpected nexus between "Marianne Wiggins" the narrator, the legacy of Edward Curtis, and even the title of the book. The author leaves behind the early themes of creating visual art and of comparing photography to painting. There's nothing wrong with the way the book treats these themes, but the unexpected plot element is what makes a seemingly predictable work into an exciting read. I don't want this to be a spoiler, so I'll stop now.