by reading the JPG’s internal timestamp before the file even enters the system.
| Usage Scenario | Quality Level | Compression (approx) | Max Dimensions | |----------------|---------------|----------------------|----------------| | Web preview (gallery) | 75–80 | 10:1 | 1920px long edge | | Thumbnail (grid view) | 60–65 | 15:1 | 400x400 px | | Print proof (low‑res) | 85 | 8:1 | 2500px long edge | | Archival derivative | 92–95 | 3:1 | original size | | Email attachment | 70 | 12:1 | 1280px long edge | Filedot AMS jpg
: These files contain calibration settings, target gamma, and white point factors. by reading the JPG’s internal timestamp before the