Print Preparation Basics
Getting an image ready to look right on paper
In This Lesson
Print Is a Different World
Everything the web lesson optimized for — small files, sRGB, screen pixels — reverses for print. Paper wants high resolution, large lossless files, and print-accurate color. A file that's perfect for a web page will look soft and small when printed, and screen colors don't map one-to-one onto ink. Getting print right is mostly about resolution and color.
Resolution and DPI
Print quality is measured in DPI (dots per inch) — how many pixels pack into each printed inch. The standard for photo-quality print is 300 DPI:
- 300 DPI — photo prints, magazines, fine detail.
- 150–200 DPI — acceptable for large prints viewed at a distance (posters).
- 72 DPI — screen only; far too low for print, will look pixelated.
In GIMP, set this under Image → Print Size (or the X/Y resolution fields), which controls how large the existing pixels print without changing the pixel count itself.
Sizing for a Print
The pixels you need follow directly from print size × DPI. Multiply the inches by 300 for each dimension:
| Print size | Pixels needed at 300 DPI |
|---|---|
| 4 × 6 in | 1200 × 1800 |
| 8 × 10 in | 2400 × 3000 |
| A4 (8.3 × 11.7 in) | ≈ 2480 × 3508 |
⚠️ You Can't Add Detail That Isn't There
Enlarging a small image to hit 300 DPI (upsampling) invents pixels and looks soft — it can't restore detail the capture never had. Start from the highest-resolution original for print; that's why Monday's masters-first organization matters.
Color: RGB, CMYK, and Profiles
Screens mix light in RGB; printers lay down ink in CMYK. The two gamuts differ — vivid screen blues and greens often can't be reproduced in ink and will shift when printed. Two practical notes:
- GIMP 2.10 works in RGB and has limited native CMYK support — for professional CMYK conversion, a print shop or a dedicated tool often handles the final step.
- Many print services simply want a high-resolution RGB (or sRGB/Adobe RGB) file and do the CMYK conversion themselves — always ask what the printer wants.
Bleed and File Format
- Bleed — if color runs to the paper's edge, extend the artwork a few millimetres beyond the trim line so cutting leaves no white slivers. Add canvas and fill the extra margin.
- Format — deliver print files as TIFF (lossless, universally accepted) or high-quality PDF. Avoid low-quality JPEG for print; compression artifacts that hide on screen show on paper.
- Flatten your XCF master to the delivery file, but keep the layered master, exactly the save-and-export habit.
The print-prep path: resolution, bleed, color, then a lossless delivery file.
Soft-Proofing
GIMP can soft-proof — simulate on screen how an image will look under a given print profile — via View → Color Management → Soft-Proofing. Loading the printer's ICC profile previews the color shift ink will cause, so you can adjust before wasting paper. It's an approximation, but it catches the worst surprises (that electric blue printing muddy) ahead of time.
🎓 Ask the Printer First
Every print service has preferences — file format, color space, resolution, whether they want bleed. One email before you export saves reprints. The professional move is to prepare to their spec, not a generic guess.
Practice Activities
- Do the math. Decide a print size and compute the pixels needed at 300 DPI; check whether your image has them.
- Set print size. Use Image → Print Size to set 300 DPI and see the resulting print dimensions.
- Soft-proof. Turn on soft-proofing with a print profile and note which colors shift.
Summary
✅ Key Takeaways
- Print reverses web priorities: high resolution, large lossless files, accurate color.
- Target 300 DPI; pixels needed = print inches × 300 — start from the highest-res master.
- Screens are RGB, print is CMYK; GIMP is RGB-centric, so ask what the printer wants.
- Add bleed for edge-to-edge color and deliver as TIFF or high-quality PDF.
- Soft-proof with the print profile to preview color shifts before printing.
Additional Resources
- Previous lesson: Web Optimization Techniques
- Next in this module: Weekend Project: Complete Workflow System
- Related: Export Strategies and Formats