One can use metallic adapters to fit M42-EOS-adapter. some are chipped. get optikxpcb from the same company in HK. get highprecison. be aware if you have Contax/Yashica-lenses to fit EOS(not relevant for this tilt-shift-adapter here). Dont buy from optixpcb. its not reliable. M42-EOS is not problem. search google for the problematic adapter (plus solution) mentioned above.