PDF Hell

Adobe's PDF format is more that 15 years old and so it should not be surprising just how different one PDF is to the next. Anyone who works with PDF files for their content and layout will have encountered PDF files that all look perfectly fine on screen but the system hides a myriad of complications that can render the file unusable.

As PDF files are the basis of most print and digital systems it is worth the time to make the PDF file as best you can for the purpose as the output is only as good as the source.

For users that are creating PDF files for digital publications, there are a few more challenges that I regularly have to overcome and a couple of these are listed here:

1) Gigantic PDFs - This is a problem that rarely bothers the print industry, but huge PDFs can severely impact the performance and distribution of digital versions. Unfortunately the only tool that makes any real difference in Acrobat is the "Save As" option which can reduce the size of a PDF a little and should also be the always be the last step of any editing (the SAVE button does NOT do the same thing). More significant size reductions though usually require 3rd-party software like those created by Apago (www.apago.com) and Enfocus (www.enfocus.com) but these solutions will not work on every file. The best answer is to see if you can encourage your designers to get rid of all of the layers and flatten everything (apart from text) before they export to PDF. I remember one motoring magazine which should have been about 20Mb was 400Mb and it became clear that the VW logo that was used throughout was a fantastically complicated EPS file that alone was 20Mb in size which should have been obvious as it Acrobat about 1 minute to render it on screen.

2) Fonts - One of the great features of PDF files is that the document can look exactly as the designer intended, but this ONLY works if these fonts are included in the PDF document itself (an option in the save screen). That is simple enough but when InDesign is used to create the PDF file, it often changes the fonts into a special type called CID or Identity-H which look perfectly normal on screen, but make the text impossible to search or index (the second option discussed here http://kb.adobe.com/selfservice/viewContent.do?externalId=329611&sliceId=2 is the only way around this that I know).

I will share more tips on PDF creation for digital in later editions of this blog.