Sources and support boundaries

Sources checked October 31, 2026. The application implements a bounded subset and does not claim complete FITS validation or confirmed account-level import acceptance.

• AstroBin: importing acquisitions from CSV. Authoritative acquisition field names and numeric limits. The sheet exports date, filter, number and duration; other documented fields are omitted.
• NASA HEASARC: FITS overview. Primary HDUs, fixed-length cards, block sizes and basic value types.
• FITS standard, version 3.0. Header/card structure, SIMPLE and END records and exposure/date examples. Used for the supported conventional header subset, not a claim that this parser implements every convention or later extension.
• AstroBinUploader. An existing directory-based alternative supporting FITS and XISF. AstroSession Sheet's distinct scope is installation-free retained-frame review with explicit decisions; superiority is unproven.

What has been checked

Synthetic tests cover malformed headers, quoting, bounded reads, truncated declared data, metadata overrides, exact grouping, exclusions and CSV syntax. No real capture corpus or live AstroBin account import is represented as verified by those tests.

Integration accounting

Siril's stacking documentation, checked November 1, 2026 UTC, distinguishes pixel rejection, image weighting and image rejection. That distinction informs the reconciliation guide. The sheet does not import a Siril sequence, interpret rejection maps or reconstruct weighting.

Start with the workflow guide, read the precise FITS subset or open the sheet.