{"lens":{"id":"canon-ef","displayName":"Canon EF","manufacturer":"Canon","flangeDistanceMm":44,"electronicProtocol":"Canon EF"},"body":{"id":"micro-four-thirds","displayName":"Micro Four Thirds","manufacturer":"Olympus / OM System / Panasonic","flangeDistanceMm":19.25,"electronicProtocol":"Micro Four Thirds"},"compat":{"lensMountId":"canon-ef","bodyMountId":"micro-four-thirds","feasibility":"mechanical","af":"partial","is":"full","aperture":"electronic","infinityFocus":"yes","adapterExamples":["Viltrox EF-M2 II (0.71× focal reducer, electronic)","Metabones EF-MFT Speed Booster / Smart Adapter"],"caveats":["Smart EF-MFT adapters pass electronic aperture and in-lens IS, and drive autofocus — but Micro Four Thirds bodies focus adapted EF glass by contrast-detect only, so AF is usable yet slower than native (hence partial).","2× crop applies on a straight adapter; a 0.71× focal-reducer variant (Viltrox EF-M2, Metabones Speed Booster) pulls the field of view back toward the EF lens's native angle and adds roughly one stop of light."],"formatNote":{"match":"lens-larger-than-body","lensFormat":"full-frame","bodyFormat":"MFT","cropFactor":2,"message":"Lens covers full-frame; body is MFT — 2× crop factor applies relative to the lens's native image circle. No vignetting; the body uses the centre of the lens."}}}