Guide
A poorly prepared PDF can cause reprints, color shifts, and wasted time. This guide walks through the settings and checks that make the difference between a smooth print run and a costly mistake.
RGB colors look vivid on screen but will shift when converted to CMYK at the printer. If your design software (InDesign, Illustrator, Photoshop) has an RGB image in it, the RIP will convert it often unpredictably. Convert images to CMYK before placing them in your layout, or at least convert them in Adobe Acrobat before submitting. If you're targeting a specific brand color, ask your print vendor for their preferred color profile and use it from the start.
When a PDF references a font that isn't embedded, the printer's system will substitute it. The result looks nothing like your original. In InDesign's export dialog, check that "Embed Fonts" is enabled subsetting is fine for body text, but for headlines and branding, full embedding is safer. If you use variable fonts or unusual typefaces, embedding is mandatory, not optional.
Most commercial print shops limit total ink density to 300–340% (CMY + K combined). Going over that can cause ink pooling, slow drying, and smearing on coated stocks. High coverage also drives up cost on small runs. Use a coverage analyzer tool to spot pages that exceed the limit before you submit. Typical problem areas are dark photographs, heavy shadow areas, and saturated background colors.
For black-heavy designs, remember that rich black (C60 M40 Y40 K100) hits around 240% adding a dark blue background on top of that can push you well over 300%.
Overlapping elements with transparency (drop shadows, multiply layers, gradients with blending modes) are a common cause of unexpected results in print. Some RIPs handle transparency well; others don't. Flattening converts all transparency into solid image data, giving the printer a predictable file. When exporting from InDesign or Illustrator, use the "High Quality Print" preset and let the software flatten as needed. If your PDF has complex layered effects, run the flatten tool before sending.
Bleed extends your design beyond the trim edge so that printing variances don't leave a white border. A minimum of 3mm (0.125 in) is standard. Crop marks tell the finisher where to cut. If you're exporting from InDesign, the Marks & Bleed panel in the export dialog handles both. Don't include crop marks unless your print vendor specifically asks for them some shops have automated cutters that use the trim box alone.
Converting text to outlines (outlining, path outlining) ensures that the type looks exactly right regardless of what fonts the output system has. The downside is that you lose the ability to edit text. For final submitted files this is fine it actually prevents accidental font substitution. Outlining also increases file size if you have many pages, so weigh the trade-off for large documents.
PDFtopia's free coverage analyzer shows CMYK ink coverage per page in seconds, right in your browser no upload required. Spot pages that are too heavy before they reach the press.
Open coverage analyzer