Choosing the right file format and scanner settings has a significant impact on recognition accuracy and upload speed. PaperSurvey accepts several common file formats, with PDF being the recommended choice for the best overall results.
Supported formats
- PDF (.pdf) - Recommended
- JPEG (.jpg/.jpeg) - Common for single pages
- PNG (.png) - Good for high-quality scans
- TIFF (.tiff/.tif) - Professional scanning
- HEIC (.heic) - iPhone photos
- HEIF (.heif) - Modern mobile photos
Recommended format: PDF
PDF is the preferred format because it combines multiple pages into a single file, compresses efficiently for faster uploads, maintains quality while reducing file size, and works universally across all scanners.
Optimal scanning settings
For the best recognition results, use these settings:
Resolution
- 300 DPI (dots per inch) is the sweet spot
- Higher resolution will not improve accuracy
- Lower resolution may cause recognition errors
Color mode
- Grayscale or Black & White
- Color scanning is unnecessary and increases file size
- Grayscale handles lighter marks better than pure black/white
File format
- PDF with compression enabled
- Multi-page document mode
- Automatic page size detection
Example scanner configuration
Here is how optimal settings look in Image Capture (macOS):
Format comparison
| Format | Multi-page | File size | Upload speed | Best for |
|---|---|---|---|---|
| Yes | Small | Fast | All surveys (recommended) | |
| TIFF | Yes | Large | Slow | Archival quality |
| JPEG | No | Medium | Medium | Single pages |
| PNG | No | Large | Slow | High detail |
| HEIC/HEIF | No | Small | Fast | iPhone and mobile photos |
Common scanning mistakes
Wrong settings
- Too high resolution (600+ DPI) wastes space without improving accuracy
- Color scanning triples file size unnecessarily
- No compression creates huge files that slow down uploads
File handling
- Mixed formats cause inconsistency; stick to one format per batch
- Huge files are rejected; the maximum size is 512MB per file
You can upload all pages in a single multi-page PDF, or upload each page as a separate file. Both work equally well. Page orientation does not matter either; pages can be scanned in landscape, portrait, or even upside down, as long as all four corner marks are visible and the content is legible.
Scanner-specific guidance
Office multifunction printers
- Look for the "Scan to PDF" option
- Enable multi-page mode
- Use the document feeder for batch scanning
Desktop scanners
- Install manufacturer software for full PDF support
- Configure default settings for consistency
- Clean the glass regularly
Mobile scanning
- Use dedicated scanning apps (not the camera)
- Ensure good, even lighting
- Check PDF export options before uploading
Other ways to upload
Besides dragging files onto the Uploads page, you can email scanned documents to your team's dedicated upload address shown on the Uploads page. Email providers usually limit attachments to about 25MB, so large batches are better uploaded directly. You can also pick files straight from Dropbox using the Dropbox button on the Uploads page.
By following these format guidelines, you will achieve optimal recognition accuracy while minimizing upload times and storage costs.