{"lens":{"id":"praktica-b","displayName":"Praktica B","manufacturer":"VEB Pentacon","flangeDistanceMm":44.4,"electronicProtocol":"mechanical-only"},"body":{"id":"t-mount","displayName":"T-mount (T2)","manufacturer":"Various (Tamron-originated standard)","flangeDistanceMm":55,"electronicProtocol":"mechanical-only"},"compat":{"lensMountId":"praktica-b","bodyMountId":"t-mount","feasibility":"requires-glass","af":"manual-only","is":"lens-only","aperture":"adapter-wheel","infinityFocus":"requires-correction","adapterExamples":["Speed Booster / focal-reducer family"],"caveats":["Flange clearance is only -10.6 mm — a plain mechanical adapter cannot reach infinity focus; a focal reducer (Speed Booster) with optical glass is required.","Speed Boosters typically widen the effective focal length (~0.71×) and add ~1 stop of light, which can be desirable on crop bodies."],"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."}}}