Find the Right Scan Resolution
Stop over-scanning or under-scanning your film. Enter your format, ISO, and output size to get a DPI recommendation that preserves grain detail without wasting storage.
Saved Profiles
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Grain Reference by ISO
Film grain size increases with ISO. Use these guidelines when evaluating scan quality:
| ISO Range | Typical Grain Size | Minimum DPI for Detail |
|---|---|---|
| 25-50 | Very fine | 1200-1800 |
| 100-200 | Fine | 1800-2400 |
| 400-800 | Moderate | 2400-3200 |
| 1600-3200 | Coarse | 3200-4800 |
| 6400+ | Very coarse | 4800-6400 |
Common Mistakes
- Scanning too low: You lose grain detail that cannot be recovered. If you need sharp enlargements, scan higher.
- Scanning too high: Files become huge quickly. A 35mm scan at 6400 DPI can exceed 1GB per frame.
- Ignoring film format: Medium format has finer grain than 35mm at the same ISO. Adjust DPI accordingly.
- Not checking previews: Always review a small section at 100% zoom before committing to a scan setting.
Understanding the Results
The recommended DPI balances grain detail with practical file sizes. Higher numbers preserve more grain but create larger files. The maximum printable size assumes 300 DPI for professional printing. If you need larger prints, scan at a higher resolution.
File size estimate is based on a 35mm frame at 4000 DPI with 16-bit color. Larger formats or higher DPI means significantly larger files.