Print Resolution

Overview

Print resolution is about effective pixels per inch at the size the image will be reproduced — not the PPI number sitting in a photo’s metadata alone. A 300 PPI image scaled to 200% on the page becomes roughly 150 effective PPI. A huge pixel count shrunk tiny can be more than enough.

Commercial offset work commonly targets about 300 PPI for continuous-tone images at final size, with tolerance down to roughly 200–250 PPI depending on viewing distance, stock, and subject. Large-format posters viewed from feet away can succeed at much lower PPI. Line art and small type in raster form need higher resolution than photos.

RIPs also relate image detail to screen ruling (lpi). A practical rule of thumb is that image PPI near 1.5×–2× the line screen supports clean halftones. Oversized megapixel files still matter for file weight, but under-resolved images create soft or pixelated results that no sharpening fully hides.

This article supersedes the shallow “low res” checklist mindset: measure effective resolution, consider viewing distance, and escalate with evidence. Pair it with the low-resolution images guide for customer conversations.

Step-by-step

1. 1. Measure at final placed size

   In the layout or PDF, note the image’s printed width/height. Compute effective PPI from pixel dimensions ÷ inches (or use preflight).

   Ignore camera “300 PPI” tags if the image is enlarged on the page.

2. 2. Match threshold to product type

   Brochures held in hand need higher effective PPI than booth graphics. Set plant thresholds by product category so CSRs apply consistent rules.

3. 3. Treat line art differently

   1-bit logos and tiny raster text often need 600–1200 PPI equivalent. Prefer vector logos when possible.

4. 4. Balance file size and quality

   Downsampling during PDF export can destroy detail if set too aggressively. Compression tools should not be a substitute for correct placement size.

5. 5. Document exceptions

   If the customer accepts soft heritage photos or intentional low-fi art, note the waiver. Otherwise reprint risk sits with the shop.

Common mistakes

• Reading metadata PPI only. Metadata does not know the layout scale. Effective PPI at final size is the production metric.
• Upsampling to “make 300”. Adding pixels in Photoshop does not restore optical detail. It may satisfy a naive preflight rule while still looking soft.
• Using one threshold for every product. Yard signs and business cards do not share the same resolution needs. Segment rules by viewing distance.