{"lens":{"id":"pentax-k","displayName":"Pentax K","manufacturer":"Pentax / Ricoh","flangeDistanceMm":45.46,"electronicProtocol":"Pentax K (KAF/KAF2/KAF3/KAF4)"},"body":{"id":"fujifilm-x","displayName":"Fujifilm X","manufacturer":"Fujifilm","flangeDistanceMm":17.7,"electronicProtocol":"Fujifilm X"},"compat":{"lensMountId":"pentax-k","bodyMountId":"fujifilm-x","feasibility":"mechanical","af":"manual-only","is":"lens-only","aperture":"adapter-wheel","infinityFocus":"yes","adapterExamples":["generic mechanical adapter ring (multiple vendors)"],"caveats":["Mechanical adapter only — no electronic communication between Pentax K lens and Fujifilm X body.","Lens has no aperture ring; choose an adapter with a built-in aperture-control wheel."],"formatNote":{"match":"lens-larger-than-body","lensFormat":"full-frame","bodyFormat":"APS-C","cropFactor":1.5,"message":"Lens covers full-frame; body is APS-C — 1.5× crop factor applies relative to the lens's native image circle. No vignetting; the body uses the centre of the lens."}}}