Sending files to your printer has lost a lot of its complexity, the universal adoption of PDF, improved software applications and automated checks have made life in prepress a whole lot easier. There are still some errors, though, that persist even in PDFs, and that could ruin your print job. Here is our list of the top seven issues with files we receive:
1. Colour usage: Files are not in CMYK when they should be, or they are when they should be in spot colours. Documents are created and then sent to us in RGB. Many files are converted without the right settings and the wrong colour profiles are embedded (The strawberries on the left were converted using an unsuitable profile making them lose contrast and look dull.) Then there are specific colour problems, like the make up of a rich black. Colour is still one of the most complex topics in print and talking about colour is necessary, though sometimes difficult, as colour perception is very subjective. If you want your printer to make your pictures look good, let them know, give them your original files and some time, if you want to do it yourself, ask them for colour settings and a press profile.
2. Image quality: Many pictures are used for online publishing and their resolution does not support print at bigger than postage stamp size. These pictures are often taken from an online environment, without supporting the quality requirements. Left in RGB, often with lossy compression (jpg), these images don't look good in print and make any publication look cheap. (The strawberries on the left were saved several times using jpg compression, making them lose definition and look pixelated.)
3. Fonts: Still way too complicated to handle, fonts can be an issue, even in a pdf workflow. They should be embedded when working with print files. All of them, always.
4. Bleeds: One of those things that a computer cannot catch is lack of bleed. You can easily check for it by looking at the edge of the page, but the number of times that our prepress has to extend a coloured area or stretch a picture is enormous.
5. Die lines - varnishes - other embellishments: They are the fun part, but they still need artwork to produce. They are often not set up correctly, often the knife line does not overprint (ie. leaves white line underneath); perforations are marked as dotted lines on the art, when there should really only be indicators instead of an actual printed line. Some of these can get a bit tricky, so the best thing might be to talk to your printer / prepress person and ask them, how these finishes should be indicated on the artwork. The worst thing to do is to send that urgent file away with none or unclear instructions and hope that "She'll be right".
6. It is not so easy to collect all relevant, i.e. final version files for a project. Sometimes it is just one pdf, but sometimes there are native files with fonts and pictures, sometimes there needs to be a database that is required for a variable data job. We need these files. Without them, we can't print (Yes, they could well be on your desktop).
7. Dummies are good, sometimes absolutely necessary. Once you have tried out, how many ways there are of folding an A4 to a DL (see our folding guide) you know why. For multi page publications we always run a laser dummy. For other jobs, especially those out of the ordinary, we love to have a folded dummy to understand, how you expect things to look in the end. Otherwise, someone will be guessing. And if it's that nightshift operator, who wants to get the job done, chances are that his idea of which one should be the back panel in a brochure might not be the same as your's.
A quick google shows that these are universal issues that will probably not go away any time soon. This makes it so important to talk to your printer and discuss what you want them to do.
Some customers want us to correct anything we see and suggest enhancements, for example to brighten up dull images. However, there are others that don't want us to touch anything and either run their file no matter what or alert them to fix problems. Either way, we need to know.