Perfect bound publications are bound by stacking text signatures, then wrapping and glueing a cover around the text, which, results in a flat spine. The nature of this style of binding is that the publication doesn’t lay flat when opened. Two important design considerations should be made to obtain optimal results in the finished product;
1) Gutter Margin– Increase gutter margin to accommodate the fact that the innermost portion of the page is lost visually (approximately 0.125” of each page will be lost). This adjustment will keep inner and outer text column margins consistent and produce the best result.
2) Crossovers– Page elements from one page that continue to the facing-page across the gutter should be spread apart to compensate for the visual loss referenced in step 1 above. Examples of adjustments that could be used are duplicating photos and shifting left-and-right, or spreading headline text apart with spaces. Important Note: inside front and inside back cover to first and last text page crossovers would utilize the same adjustment as text pages, however, the adjustment value would be based on 0.1875”, which, represents the side-glue / hinge-score area of the cover.
Crossovers between the inside covers and the first or last text page require an allowance to compensate for the hinge score of the cover. For instructions on this and how to build perfect bound covers, please read Tech Note 006.