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Basics of Imposition
DocBuilder Pro reorders imposed pages automatically according to your choice of
binding method, which can save a significant amount of time and effort. Consider, for
example, what must be done when a book that was to be saddle stitched exceeds the
bindery’s maximum page count and must be reimposed as a perfect-bound book. To
redo the imposition by traditional means would be labor-intensive; with DocBuilder
Pro, it takes only moments.
Shingling and creep
All books and brochures use a sheet that is folded to create separate page areas. Because
the sheet itself has some thickness, each fold causes a very small incremental shift in the
location of the edge of each page relative to the others. The result is that the edges of
pages furthest from the saddle’s innermost fold seem to move away from the edges of
pages closest to the innermost fold. As the number of pages in the saddle increases, so
does the amount of this shift, which is known as shingling. To counteract the effects of
shingling (illustrated in an exaggerated manner in the following figure), the bindery
trims the edges of the finished book to a common edge.
Trimming the bound pages resolves only half of the problem, however—as the edges of
pages move, so do the content areas imaged on them. The apparent shift of content
area caused by folding a sheet multiple times is known as creep or binder’s creep. The
effect of creep is that the content area of pages closer to the innermost fold in a saddle
appear to move towards the outer margins of the page.
Shingling