Print ready file: the setup checklist

Print ready file checklist

Go down this list once before you send anything. Each item is explained below.

CMYK versus RGB

Screens make color from red, green and blue light (RGB). Printing uses cyan, magenta, yellow and black ink (CMYK). Carleton University's print shop says monitors use RGB, which suits digital designs, and that using RGB for print can cause color inconsistencies. Indiana University's printing services asks for "the CMYK color space for optimal color output."

The reason colors shift is that light on a screen and ink on paper cover different ranges of color. A very bright screen color can print duller on paper.

The fix is to set the document to CMYK before you design, so the screen gives you a closer preview of the printed color while you work. A screen still cannot show ink exactly, so ask us for a printed sample when a color has to match. If you convert at the end, look at the file again after the conversion.

Resolution: 300 pixels per inch at final size

Indiana University's printing services says, "For best print results, make sure all the images in your project are at least 300 dpi," and warns that scaling an image up lowers its effective resolution. Carleton says 300 DPI for most projects and a range of 150 to 300 for pieces 8.5 x 11 inches or larger. People say dpi, and design programs say pixels per inch. For a digital image they mean the same thing here.

To get the pixel size an image needs, multiply the printed inches by 300. To check an image you already have, divide its pixels by the printed inches. A photo that is 1,200 pixels wide and printed 6 inches wide is 1,200 / 6 = 200 pixels per inch, which is below 300. A small logo copied from a website is one to check. A wall poster read from a few feet away looks sharp at 150, as our poster sizes guide explains.

Bleed and safe area

Add 0.125 inch of bleed on every side and keep text at least 0.125 inch inside the trim. The file ends up 0.25 inch larger than the finished piece in each direction, so a 4 x 6 postcard is a 4.25 x 6.25 inch file. Our guide on what is bleed in printing covers how to set it in each program and the mistakes we see most.

Fonts: embed them or outline them

A font that is not inside the PDF gets swapped for another one when the file opens on a different computer, and the text can reflow or change shape. Carleton says to "Embed all fonts within your PDF to avoid font substitution issues." Indiana says, "When possible, send your pdf document with outlined fonts, or flattened."

Outlining turns letters into shapes, so they cannot be swapped. The tradeoff is that you can no longer edit that text, so keep your original file. Embedding keeps the text live, and a design program can do it for you on export.

Exporting the PDF

In InDesign or Illustrator, export a PDF with bleed and crop marks on. In Canva, turn on File, Rulers and guides, Show print bleed while you design. To download, choose Share, Download, set File type to PDF, pick the Print preset, then open Advanced Settings and turn on Crop marks and bleed, which is off by default. In Word or PowerPoint, make the page the bleed size and save as PDF. Then open the PDF yourself, zoom in, and check that the fonts look right, the photos are sharp and the background runs to the edge.

PDF/X is a family of ISO standards (ISO 15930) for handing a file to a printer. The Library of Congress format description says PDF/X-1a:2001 is "for complete exchange for CMYK data" and lists, as a key rule for that kind of exchange, that "all fonts and images must be embedded." Carleton recommends PDF/X-1a:2001 for the best quality. If your program offers a PDF/X preset, ask us which preset we prefer before you export.

Problems to check for

A photo pulled from a website is the resolution problem to watch for. It looks sharp on a screen and prints soft at full size. If the image is too small, find the original from the camera or the designer, because stretching it adds no detail. A logo is better sent as a vector PDF when you have one, since vector art stays sharp at any size.

The others are RGB files that print duller than the screen, missing bleed on a design with a background color, and a PDF exported without the bleed the document had set. If you are not sure about any item above, ask us before you send the file.

Sources used in this guide

Indiana University printing services, Preparing a File (printing.indiana.edu). Carleton University print shop, Best Practices for Print Files (carleton.ca/theprintshop). Library of Congress, format description of the PDF/X family (loc.gov).