FAQ

No. Scanning is fully local — image data, file paths, and scan results are never uploaded.

Indexing reads FITS headers only. To build a Target Thumbnail, Photon Ledger additionally reads the pixel arrays from a small sample of light frames per target so it can align and stack them into a preview. All of this happens locally — nothing is uploaded.

On a local SSD, expect 1,000–4,000 frames/second. On a 1 GbE NAS, 200–500 frames/second. Bottleneck is small-file metadata, not raw bandwidth.

Roughly 1–2 kB per indexed frame. A 100,000-frame archive lands around 150–200 MB on SQLite.

Standard FITS (.fit, .fits, .fts) and fpack tile-compressed FITS (.fz, Rice or GZIP tiles, as written by many observatory pipelines and capture programs with “compressed FITS” enabled) — headers and thumbnails both work on compressed files, since 1.4.3. Multi-extension FITS is read from its first image extension. Whole-file gzip (.fits.gz) is not supported: run gunzip or fpack first.

None hard-required. Photon Ledger does its best with whatever is present. For full functionality, OBJECT, FILTER, EXPTIME, DATE-OBS should be set.

No. Photon Ledger is free, with every feature included — no license file and no frame cap. If it saves you time, you can support development.

Yes. Read-only access to your FITS files is enough. Make sure the share is mounted before you scan.