To those of us who don’t use PDFs for artworking, a PDF is a PDF is a PDF. They’re all the same, surely? But say that to a printer and they’ll give you some very dark looks indeed.
You see, one major source of headaches for anyone who handles artwork at any printing services company, is artwork delivery. Not only is the PDF pretty much the de-facto standard format in which to provide artwork to printers, but most will point you towards the street should you darken their door clutching an InDesign or Quark file.
They need you to provide artwork in the correct format to stop errors creeping in. PDFs are particularly useful because they include lots of information within the file – including fonts, images, text and layout – pretty well all the information required by a printer to print the job.
Which PDF Version?
So you need to output your artwork to a PDF before you approach your commercial printer. However, not all PDFs are created equal. You see, the PDF format (standing for Portable Document Format) has gone through several iterations to become the uniquitous document format it is today – adding in support for new features as they were demanded by specific industries.
The latest version in development is PDF v2.0 but the first version came out in 1993 as version 1.0 and has already undergone 10 revisions since then to arrive at V1.7 last year (I know the maths doesn’t add up, but you’ll have to take that up with Wikipedia).
So there was a point in time when most printing organisations drew a line in the sand. And for many, that was when the PDF format contained enough print-ready data to make the format stable and viable – and that was when PDF V1.3 came out.
(here’s a handy link to the PDF reference document for you – all 696 pages of technical nonsense (you can thank me later!)
PDF Printing Guidelines
So, it’s important to check with your printing services company or commercial printer to get a copy of their PDF artwork guidelines before you send your artwork through. Here’s a download of Webmart Proofing Guidelines 2011 so you can see the kind of document to look out for.
Notice the checklist (in the doc and, for your delectation, below). We’re entering a particularly technical arena here so it’s important that you try and comply with all the items otherwise you may be disappointed with the end results. Sorry it’s so long but it’s compiled from experience – everything on the list has (and does!) go wrong.
- Trims/crop/register marks should be set to appear at 100% of document trim size.
- PDFs should be saved and supplied as v1.3 (Pass4 Press v8 stipulates PDF version 1.3, later versions may cause problems, particularly with transparency).
- All images and text should be embedded in the PDF, and not linked through OPI.
- All images should be saved as CMYK, and not RGB.
- Spot Pantone colours should be supplied as a 5th colour within the artwork.
- Cutter guides should be supplied as a 5th colour not to print, or as a separate file correctly sized and positioned.
- All halftone image resolution should be a recommended 300dpi. Line art should be 1200dpi.
- Any transparencies should be flattened.
- All pages require 3mm bleed on all sides. Perfect binding will require an additional 10mm on the spine.
- If not bleeding off – all live matter (text & images) should be 5mm inside of trim.
- ICC profiles should not be used. Our chosen suppliers do not apply colour management apart from to compensate for press dot-gain.
- Solid black areas should be set as ‘Rich Black’ (Rich Black = 50% Cyan underlay + 100% Black) unless part of a CMYK image. If dark CMYK images are used, please refer to the UCR & GCR settings in the Pass4Press document.
- Fine lettering, lines, text should be set as single colour only. If two or more colours are used then a minimum 9pt is recommended.
- Fine type and detail can also be problematic when reversing or ‘knocking-out’ out of solid background colours, no less than 12pt is recommended and serif fonts should be avoided unless suitably sized.
- Pages should be centred (horizontally and vertically) within the document with a common point of origin.
- Pages should be supplied individually as single pages – not as designer spreads.
- File names must be consistent, contain a name or number to identify the project and be correctly folioed, e.g. Webmart_32pp_ p01.PDF.
- Revised amended pages should be additionally marked ‘REV’ e.g. Webmart_32pp_ p01_REV.PDF
Anything we’ve missed or any anecdotes over what can go wrong? We’d love to hear!
More to come on what can go wrong with your PDF (even PDF’s aren’t infallable!)