What Is Prepress?
A MegaColorUSA Guide to Better Print Files
Prepress
Made Simple
Great printing starts before the first sheet is ever printed. Visual examples make it easier to submit better files, avoid delays, and get beautiful results.
What Is Prepress?
Prepress is the quality-control stage between creating artwork and producing the finished piece. Images, colors, dimensions, bleed, fonts, and other details are checked so your design prints as intended.
DPI vs. PPI
PPI describes digital-image resolution. DPI describes an output device such as a printer. Use the highest-quality original image available.
How CMYK Creates Color
Tiny dots of Cyan, Magenta, Yellow, and Black ink work together to reproduce full-color images in print.
Halftone Dots
Your eye blends halftone dots into smooth tones, shadows, and gradients.
Color Separations
A full-color image is separated into individual plates. Each plate holds one ink color.
These four separations print together to create the final image.
Spot Color
A pre-mixed ink delivers an exact brand color or special effect instead of building it from CMYK.
Spot colors can print at full strength or as lighter tints.
Knockout vs. Overprint
In Register vs. Out of Register
What Is Trapping?
Trapping adds a tiny overlap between adjacent colors to prevent white gaps.
A small overlap keeps colors looking solid even with slight press movement.
Dot Gain
Printed dots can grow slightly, making images darker. Professional color management compensates for it.
Moiré Pattern
Unwanted waves can appear when repeating screens interfere. Original digital files help prevent it.
What Is a RIP?
A Raster Image Processor converts artwork into data the printer can understand.
Print-Ready PDF
Check size, resolution, color, bleed, fonts, overprints, and layout before submitting.
Prepress Checklist
Confirm final size, bleed, image quality, colors, embedded fonts, and a clean PDF.