I’m designing a cookbook in InDesign using templates from blurb.com similar to the one below. If I want a photo or a piece of text to be aligned to the centre of the page when the book prints, is it better to align it central to the live work area or to the actual page trim size? My gut says align relative work area but I’m not 100% sure…
You’re right, you need to align your artwork in the live work area (yellow) for best results, NOT the page.
You can look at most hardcover or paperback books, you will notice they are easier to read if there’s more room in the middle. And because of the binding, when you open a book the central part where the binding is will curve your sheets and give already the impression that margin is shorter than the outside one; for this reason you SHOULD NOT align your artwork on the binding or the total width of the page! You either center it in the live area or on the outside edge (from the limit of the inside margin to the trimmed outside edge of the book.)
Another reason for not aligning to the middle part is: When people read books, they usually don’t like that curved shape the binding gives to the pages and they will open it even more to flatten the areas where the text is; this will create pressure on the binding and if it’s a cheaply made one, the pages will start to detach from it over time. It’s worst on perfect binding and books with a lot of pages. To avoid this tension, it’s better to keep your artwork closer to the outside edge and not too much on the inside one. The thicker the book, the further you should be from the center area. By thick, I mean more than 200 pages.
When you work in that kind of template, consider that live area in yellow as your whole page and use that to center your artwork. If you can do bleed, then you still center your artwork in that yellow area but you can add non-important elements in the pink zone.
Blurb has already prepared their templates to be optimal for their printing and binding, you should simply trust them. It may look misaligned on your file but it will look great once printed! In fact if you center your artwork on the total width of the page, it will look misaligned once printed.