{"lens":{"id":"canon-fd","displayName":"Canon FD","manufacturer":"Canon","flangeDistanceMm":42,"electronicProtocol":"mechanical-only"},"body":{"id":"l-mount","displayName":"L-Mount","manufacturer":"Leica / Panasonic / Sigma","flangeDistanceMm":20,"electronicProtocol":"L-Mount"},"compat":{"lensMountId":"canon-fd","bodyMountId":"l-mount","feasibility":"mechanical","af":"n/a","is":"n/a","aperture":"manual-ring","infinityFocus":"yes","adapterExamples":["generic mechanical adapter ring (multiple vendors)"],"caveats":["Mechanical adapter only — no electronic communication between Canon FD lens and L-Mount body."],"formatNote":{"match":"match","lensFormat":"full-frame","bodyFormat":"full-frame","cropFactor":null,"message":"Lens image circle (full-frame) matches body sensor (full-frame) — no crop or vignetting concern."}}}