Image shadowing

Does anyone know if there's a way to turn off the image shadowing? It really makes it hard to see some of the smaller images.

On that note, is there any rhyme or reason to the size of the images---especially for books. I assume that it is tied in some way to the book binding so that paperbacks look like paperback sitting next to hardcovers. However, some of my paperbacks are huge and others are tiny. Any way to just make them sorta the same size (i.e. take full height on the shelf)?