The exiftool branch of the date waterfall now pulls raw strings with
group prefixes (one `exiftool -j -q -G1` subprocess per batch, no
`-d %s`) and classifies each candidate:
- zoned strings (own offset / Z) are true instants;
- naive strings from container groups (QuickTime/Track*/Apple) are
UTC-rendered creation_time fields -> true instants (utc_direct).
Running them through the camera wall-clock cascade was the
"videos off by 4-5 hours" bug: it reinterpreted a UTC instant in
the server zone;
- naive strings from photo-EXIF groups are camera wall clocks and run
the offset cascade (OffsetTime* pairing + GPS evidence pulled in
the same exiftool pass).
The legacy date_taken column stays byte-identical to the old
server-local interpretation (reproduced in Rust, DST-aware); the
new-contract date_utc / camera_offset_minutes / date_taken_tz_source
columns carry the true instant.
Manual date edit (POST /image/exif/date) reinterprets the
naive-as-UTC epoch the client sent as a wall clock in the user's
display zone (camera_tz::manual_date_resolution, tz_source =
'manual'), snapshots the pre-override new-contract triple next to the
existing legacy snapshot pair (3 new columns, migration
2026-09-25-000000), and revert restores both pairs.
ADR-0001 records the container-date finding; CLAUDE.md date-pipeline
section updated.
Cameron Cordes
d2263be6ac