Preflighting (or preflight checking) is the process used in the graphic arts, print and publishing industries to check certain document types to make sure they are suitable for output. The process of preflight checking a document can take place manually within certain software applications or automatically within a workflow, which dramatically reduces the risk of output problems after a file has been rasterised (RIPped), one of the major causes of print and production delays.
The preflight process checks for a range of potential problems such as:
- Missing images and graphics
- Inaccessible fonts
- Corrupted fonts
- Incompatible font formats
- Incompatible image files
- Incompatible colour formats (some RIPs have problems processing RGB images, for example)
- Resolution issues
- Presence of the correct colour profiles
- Corrupt Images
- Incorrect page-layout, document size, margins, bleeds etc...
- Compatibility with the output device e.g. inkplates, colour separations
- information all fit within the constraints of the output device and match the client specifications
- confirm that the correct colour separations or ink plates are being output
Other, more advanced pre-flight steps might also include:
- removing non-printing data, such as non-printing objects, hidden objects, objects outside the printable area and objects on layers below
- flattening transparent objects into a single opaque object
- converting fonts to paths
- gathering embedded image and graphic files to one location accessible to the system
- compressing files into an archive format
Preflight software is flexible in that it enables the user to define set 'file checking' criteria unique to specific output requirements. If any files checked deviate from these preset criteria, depending upon the software package used, a variety of reports can be generated to highlight the problems. Some preflight software packages also provide error correction capabilities depending upon the nature of the problems identified.
Preflight checking of files is a fundamental part of the creative process and without it, invariably output problems can be missed. This then results in significant costs and delays. Preflight software generally achieves a significant Return on Investment as it saves employees' time as well as print materials and equipment.