Method — where every compatibility fact comes from
How this dataset is built and audited: every claim cites a verified source with a date, unsupported combinations are labeled rather than guessed, and the tool never fabricates a compatibility answer.
What this site is
LensCompat answers one question with evidence: does this Canon EF-family lens work on this Canon RF body, and what do I need to know? The dataset is the asset; the lookup tool and these guide pages are views over it. Nothing on this site is a hand-written compatibility claim — every rendered verdict resolves through the same engine over the same versioned, source-cited dataset.
Provenance discipline
- Every fact row carries
source_ids; every source carries a verified URL (fetched, content read), a kind, and anaccessed_atdate. - Facts that could not be verified are never inferred to complete the dataset. The engine reports those combinations as unsupported_claim — explicitly.
- If a fact changes, the new fact gets a fresh source row with a new verification date; old rows stay as the provenance trail.
- A build-time validator (
npm run validate) refuses to pass a dataset whose rows lack sources or reference unknown source ids, and smoke-tests every lens × body combination for claim coverage.
Source kinds
| Kind | Count | Meaning |
|---|---|---|
official | 48 | Canon-published (product pages, support documents, press, Camera Museum) |
consensus-third-party | 10 | respected review / spec references (e.g. DPReview) |
manufacturer | 0 | other manufacturers (adapter makers) |
community | 0 | forums and community posts — lowest confidence, still citable |
Current dataset
| Collection | Rows |
|---|---|
| Sources | 58 |
| Camera bodies (RF / RF-S) | 13 (9 full-frame · 4 APS-C) |
| Lenses (EF / EF-S / TS-E / MP-E) | 31 |
| Adapters | 1 family (standard + control-ring + drop-in-filter) |
| Class rules | 3 |
| Caveats | 3 |
Dataset sources last verified 2026-09-07. The full source ledger is public on the sources page.
Honest limits
- Corridor 1 only. This dataset covers Canon EF-family lenses on Canon RF bodies via the official adapter. Nikon F→Z and Sigma MC-11 corridors are not implemented; those combinations return no claim.
- Effective crop resolution is body-dependent and not stated in the sources we verified — the tool says so instead of estimating megapixels.
- Per-lens mechanical specs (tilt/shift ranges, magnification, weights) are not yet in the dataset and are not claimed.
- Verification is point-in-time: pages are cited with the date their content was fetched. Canon could change a page after its
accessed_at; re-verification adds a new source row.
Retailer links
Where a verdict needs an adapter, the tool offers plain product-search links to two retailers
(marked rel="sponsored" where applicable). The compatibility answer never depends
on the retailer links — they appear only after a verdict resolves, and the tool works fully
without them.