Pre Press
Chapter 2 – THE PRE-PRESS DEPARTMENT
All file preparation, separation and platemaking typically take place in the pre-press department. When a designer releases their digital files for print, the first step is for the prepress department to analyze them for any potential issues. This is called preflighting. At this stage, pre-press will communicate the issues to all parties involved and make suggestions on how best to separate the file for print. When all issues are resolved the art stage begins.
THE ART STAGE
For spot color work- A pre-press specialist manipulates the file to separate as determined at the preflight stage. Then the correct dieline is applied, sufficient bleed is added and the file is proofed to the customer. Text, color and layout changes are also done at this stage.
For 4 color process work: Apart from the steps above, the file is then trapped (see explanation below) and a high end proof is generated that simulates how the 4 color process areas will print on press. If a color target has been sent by the customer then the specialist will begin the color correction stage in an attempt to match what has been supplied.
COLOR CORRECTION
At this stage the files are manipulatedi in a photo editing application such as photoshop until they match the supplied target as best as possible.
Reasons for color correction: Most color targets supplied are generated by the customer or designer on low end, continuous tone laser proofers. They are usually printed on a commercial substrate with no simulation of specific press conditions. Macaran’s high end proofing device, on the other hand, has been profiled to replicate pressroom variables such as ink and substrate hue, saturation, density, dot gain, overcoat and laminate effects.
TRAPPING
Due to the speed and mechanics of an average flexo press, color registration can become a challenge for even the most seasoned press operator. To compensate, pre-press builds trap into each separation. Trap is the overlap of adjacent colors in order to hide or minimize the effects of press movement. Without trap, colors that are intended to touch may print with a gap between them.