The Bleed That Vanished in the Print Shop
You deliver a 32-page saddle-stitched booklet to a printer as a PDF. The designer set up the document at 210 × 297 mm with facing pages, but the bleed was left at the default 0 mm because the background art was placed as a full-page image frame snapped to the page edge. On press proof, the printer reports thin white slivers along the outer edges of several pages and asks for a re-export with 3 mm bleed. You open the file and notice the background frame's bounding box sits exactly on the page edge, and the image inside is scaled to 100%. The document has 32 pages, and re-placing art on every page is not an option under the deadline.
1. Why does simply adding 3 mm bleed in Document Setup and re-exporting not fix the slivers, and what is the correct sequence of changes?
Read the worked answer
Adding bleed in Document Setup only changes the page geometry and what the exporter offers to include; it does not extend existing artwork. The background frame still ends at the trim edge, so there is nothing beyond it to bleed.
Correct sequence:
- Set bleed to 3 mm in Document Setup (or File > Document Setup) so the document knows about the bleed area.
- For each affected page, enlarge the background frame so its edges extend past the trim into the bleed area - either by dragging with the bleed guides visible (View > Guides & Grids, enable Show Bleed) or by setting the frame's position/size numerically in the Transform or Control panel.
- If the image inside the frame is scaled to fit exactly, re-fit it (Object > Fitting > Fill Frame Proportionally) so enlarging the frame doesn't reveal empty space.
- Export with Use Document Bleed Settings checked in the PDF export dialog, or verify the bleed values in the Marks and Bleeds section.
The key judgement is that bleed is an artwork problem first and an export setting problem second.
2. The printer also asks whether the booklet should be exported as single pages or spreads. What do you check before answering, and what do you recommend?
Read the worked answer
Check two things: (1) whether the printer's imposition workflow expects single pages (most commercial printers do - they impose themselves), and (2) whether any content crosses the spine in a way that requires spreads for visual verification.
Recommendation: export as single pages with facing pages still enabled in the document, because the printer imposes the saddle-stitch signatures from single-page PDFs. Exporting spreads can cause the printer to re-impose incorrectly or reject the file. If the designer needs to proof the spread appearance, do that as a separate low-res spreads PDF for internal review, not as the print deliverable. Also confirm the page order starts on a right-hand page so the 32-page count divides cleanly into signatures.