I’ve written in the past about camera-ready art and am always talking about the need to provide properly formatted files to get the best results out of a print project. We even ask for high-resolution PDFs on our upload page. But the thing about PDFs is that they have become so versatile and detailed that is it easy to create a PDF which will not print as expected.
A few years ago there was a push to come up with a solution. The end result was a set of rules for PDFs which were meant to be printed. This set of rules is called PDF/X, and the profile we’re interested in most here is PDF/X-1a.
What is a PDF/X-1a file? It is a PDF to which several rules and restrictions apply to make the printing process more predictable. (Notice I didn’t say “seamless”!) Here are the most important of these rules:
1. All fonts must be embedded in the file. (You’ve heard me rant about fonts before!)
2. All color data in an X-1a file must be grayscale, CMYK or named spot colors.
3. OPI (Open Prepress Information) is not allowed in PDF/X-1a files. OPI is a method of creating low-resolution placeholders for high-resolution images (linked objects).
4. X-1a files can’t include music, movies or non-printable annotations. If there are annotations or comments in the PDF, they should be moved outside the bleed area.
6. X-1a files contain the following extra markers that define the bleed and trim area:
a. A MediaBox defines the size of the entire document
b. Either the ArtBox or the TrimBox defines the extent of the printable area
c. If the file is to be printed with bleed, a BleedBox must be defined. It must be larger than the TrimBox/ArtBox, but smaller than the MediaBox.
Like I said, there are more rules but this post isn’t meant to be a lesson. Instead, please consider it a request for you to send us your files in this format!
You might be thinking, “How am I going to create a PDF/X-1a file?”
It’s actually easy. Just have Adobe Acrobat 7 or higher installed and you can use the X-1a profile in the Distiller to create a compliant file. Just go Print –> Adobe PDF –> Properties –> Adobe PDF Settings Tab –> Default Settings –> PDF/X-1a:2001. Once you get the hang of this process you will have much greater confidence that your project will print as you expect.