When displaying images across the binding, there are some important watchpoints to be aware of. As our hinged layflat books are traditionally bound, each left and right page is a separate piece of paper. Due to slight variations in printing registration front and back, and also small tolerances in trimming the pages, there can be a mm or two variation in the vertical or horizontal positioning of each left and right page. Therefore it is strongly advised not to put important and/or high contrast/linear elements in the centre of the spread. Similarly, it is best not to place text across the binding, unless you are certain that the seam will fall between words. As a general rule it is best to keep the focus of the image/spread to the left or right of the hinge area.
Also note that A3 books have slightly different printing process. As a result we strongly recommend no backgrounds, or only pale backgrounds for A3 layflat books.