{"lens":{"id":"pl","displayName":"PL (Positive Lock)","manufacturer":"Arri (industry standard)","flangeDistanceMm":52,"electronicProtocol":"mechanical-only"},"body":{"id":"m42","displayName":"M42 (Pentax / Praktica screw mount)","manufacturer":"Various","flangeDistanceMm":45.46,"electronicProtocol":"mechanical-only"},"compat":{"lensMountId":"pl","bodyMountId":"m42","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 PL (Positive Lock) lens and M42 (Pentax / Praktica screw 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."}}}