Most print problems trace back to the file rather than the press. Wrong color modes, missing bleeds, unlinked fonts, and low resolution are the most common — and most preventable — issues we see at our Anderkilla press floor.
The Prepress Checklist
Use this checklist before submitting any artwork to your printing press:
1. Color Mode: CMYK Only
Print presses do not use RGB. Your file must be in CMYK (Cyan, Magenta, Yellow, Key/Black) color mode. RGB files will produce unpredictable color shifts — especially blues, greens, and vibrant reds.
- In Adobe Illustrator: File > Document Color Mode > CMYK Color
- In Adobe Photoshop: Image > Mode > CMYK Color
- Convert early — color profiles change during conversion
2. Resolution: 300 DPI Minimum
All raster images (photos, textures, gradients) must be 300 DPI at actual print size. A 100 DPI image that looks sharp on screen will print blurry and pixelated.
- Check in Photoshop: Image > Image Size > Resolution
- 72 DPI = screen only, never print
- 150 DPI = acceptable for large-format banners viewed from distance
- 300 DPI = standard for all print materials
3. Bleed Margins: 2-3mm
Bleed is the area beyond the final trim edge. Any background color, image, or pattern that touches the paper edge must extend into the bleed zone.
- Standard bleed: 2mm to 3mm on all affected sides
- Safe zone: Keep text and important elements 5mm (0.2") inside the trim line
- Visiting cards: 3.25" x 2.0" with 0.2" safe margin
4. Font Handling: Outline or Embed
Fonts not embedded in your file will substitute with default fonts during printing. This changes spacing, line breaks, and overall design.
- In Illustrator: Select all text > Type > Create Outlines (Shift+Ctrl+O)
- In InDesign: Package file with fonts included
- In PDF: Ensure fonts are embedded (check Document Properties)
5. File Formats
Accepted formats for offset printing:
- Adobe Illustrator (.AI) — Preferred for vector artwork, logos, and text-heavy designs
- PDF/X-1a — Industry standard for print-ready PDFs with embedded fonts and CMYK
- Adobe Photoshop (.PSD) — For photographic artwork at 300 DPI CMYK
- EPS — Legacy format, still accepted for vector graphics
6. Black Color Specifications
Rich black vs. standard black matters for large solid areas:
- Standard Black: C:0 M:0 Y:0 K:100 — For small text and fine lines
- Rich Black: C:40 M:30 Y:30 K:100 — For large solid areas (darker appearance)
- Never use rich black for small text — it causes registration issues
7. Image Transparency & Effects
Flatten transparency and rasterize complex effects before submission:
- Transparency: Flatten all layers before export
- Drop shadows: Rasterize or expand
- Gradient meshes: Convert to raster at 300 DPI
The Free Prepress Service
At Shahid PrintShop, our senior prepress team audits every customer file at 300 DPI CMYK and verifies dieline margins for free before a single plate is burned. This catches problems before they become wasted paper.
Frequently Asked Questions
What resolution do I need for print files?
All print files must be 300 DPI (dots per inch) at actual print size. Files below 300 DPI will appear pixelated or blurry in the final printed product.
Why must files be in CMYK mode?
Print presses use CMYK (Cyan, Magenta, Yellow, Key/Black) ink colors. RGB files designed for screens will shift colors unpredictably when printed. Always convert to CMYK before submitting.
What bleed margin do I need?
Standard bleed is 2mm to 3mm on all sides that extend to the edge of the paper. This prevents white edges from showing after trimming.
What file formats do you accept?
We accept Adobe Illustrator (.AI), PDF (PDF/X-1a preferred), Adobe Photoshop (.PSD), and high-resolution EPS. Fonts must be outlined or embedded.
Is prepress file checking really free?
Yes. Shahid PrintShop provides free 300 DPI CMYK prepress file verification for every order. We check color mode, resolution, bleeds, font embedding, and dieline accuracy before any plate is burned.