This lesson explores pre-flight checks and the ripping process, as well as the issues that might occur between document creation, managing and printing.
There is much more to publishing a document than just clicking print.
Files in desktop publishing may have embedded information, or may link to information outside of the document.
The more information is embedded the bigger the file becomes and more difficult to use or edit. Whereas linking external information to the file keeps its size down and makes it easier to edit.
Ultimately the file will need to have all the information put together in one way or another to be proofed or printed. The more complex a document the more important quality checks are.
Problems with Outputting
PostScript is a page description language invented by Adobe which, when translated through a RIP, forms the desired image on an output device.
It was the first technology of its kind, in that it provided a means of bringing together text and graphic data into a single page file.
PostScript has developed over time and the features available and the compatibility of a RIP to process Post- Script files depends on the level (eg PostScript Level3)
Format problems are bad enough but what if the file’s content has problems? If the fonts used in the document are not available, or if they come from a different family, the file won’t process properly. Or, if the file does make it to the output device, there could be weird aberrations that you notice on the page, but that weren’t obvious on proof or press.
Keeping track of colour is particularly tricky. Sometimes a slab of black text can mistakenly get defined as colour data, with words built out of the four process printing colours.
Mixed together, Cyan, Magenta and Yellow make Black. At least they’re supposed to. Few printing inks are as pure as they ought to be, so mostly a black made out of cyan, magenta and yellow comes out a murky brown.
Using a pure black instead solves the problem, so any text or line art on the page that is meant to be black, should be printed with black ink. Spotting a messed up black before the damage is done is something preflight checking software will pick up.
Another tricky problem is colour data conversion. Digital files are defined with mathematical values, according to whether they are based on mixes of RGB (red, green and blue), or CMYK (cyan, magenta, yellow and black).
These numbers are obviously different according to whether the image is made up of RGB values or CMYK values. But printing presses only work with CMYK, so if an image is defined with RGB values, it won’t even be slightly attractive on the printed page.
Besides providing insurance, so that bad files don’t make it through the workflow, pre-flight checking software can often guide people and help them better understand what went wrong and why.
Don’t rely on the software
Before files enter the production workflow, you should go through some simple checks on the file yourself. That way you will pick up and correct any obvious mistakes before your files go any further.
Make sure you cover the basics such as that CDs are readable and your monitors and proofers are calibrated. Make sure you know where the content is coming from, and what will need doing to get it ready for printing.
Using consistent naming conventions is just about the easiest means of keeping track of files. Names can be customer codes, dates and deadlines, publication titles, anything as long as it works.
It’s also sensible to use file extensions as well, a concept familiar to most Windows users but one that isn’t common amongst Mac operators.
A file extension, such as .doc, .tif, .jpg, .eps or .xsl, tells your computer’s operating system, say Windows XT or Mac OSX, which software was used to create the file, and how to go about opening it.
Missing images & illustrations
Given the complexity of modern workflows, it is easy to lose track of images. Layout software such as Quark XPress or InDesign puts a low-res proxy version of an image on screen, with a link to the high res version residing elsewhere on the system.
On the monitor it looks as if the image is there but in fact it isn’t, so it’s vital to keep all high res images and illustrations organised and accessible. That way the correct files are always where they should be, throughout the production process.
Working with images
It’s pretty obvious when an image is missing, but images with too little resolution aren’t so easy to identify.
When digital files enter a pre-press department, the most common problem is missing fonts or images or both.
Keeping up with the digital housekeeping can help considerably to keep fonts organised. For convenience and to avoid cluttering up the system folders on individual computers, you might keep fonts on a server.
Operating systems such as Mac OSX or Windows store and organise fonts differently, so make sure you understand how your particular operating system manages fonts.
Software tools for keeping track of fonts used, and deleting duplicates and malfunctioning fonts help make font management less of a headache. Extensis Suitcase Server for example keeps track of the fonts used in a file, and makes sure all fonts in circulation are legal.
TrueTypes fonts can cause problems in PostScript and PDF based workflows, so avoid them whenever you can. If you have to use a TrueType font, test that it works with your workflow, and check with your printer to make sure it outputs properly. Most font related production errors can be avoided by sticking with PostScript Type 1 or the new generation Open Type fonts.