Avoid a border or rule line close to the trim edge.
Including a border in your file makes any trim variation much more noticeable. Per the File Creation Guide, for cover art, we recommend at least .25” from the trim mark for perfect bound books. For Case Laminate books, we recommend at least .25” from the edge of the board. For interior pages, we recommend at least .50” from trim marks.
Avoid a background or images stopping exactly at the spine.
Any variation in the horizontal binding position of the cover is much less noticeable on a cover design than has an image or same color that wraps from the front cover, across the spine, and onto the back cover. To avoid emphasizing the allowed variance of .0625” when binding a cover, we recommend that there be no ‘hard’ breaks of images or background color at the spine fold. Having color or image breaks at the spine highlight any variance, even those within the stated tolerance.
Always use the default setting PDF/X-1a:2001.
If black text looks light this is often due to RGB or CMYK ‘black’ text. Most often black text looks light due to the presence of an ICC color profile. Using the default PDF/X-1a:2001 setting will address this issue.
Minimize “popping” matte laminate at the spine by adjusting the TAC.
Laminate popping usually happens on dark covers (dark blues, dark reds) and is sometimes caused by the cover file being above 240 TAC (density). To avoid this, reduce the TAC to be 240.
Use adequate bleed dimensions.
Lightning Source requires an interior file have 1/8” bleed on the three trim edges. We do not accept files with bleed on the bind side of the page. When a file is stored, it is cropped down to the bleed dimensions. ‘Extra’ bleed would merely be cropped out of the file before it gets to the printer.
For more information about file creation please see our file creation guide.