I had hesitated to try this for so long, but finally today a brave EOSHD reader sent me a tweet saying he had fitted his BMCC Speed Booster (with protruding rear-glass) on his GH4. It just goes straight on. First a BIG disclaimer. Speed Booster adapters have adjustable glass which can sit closer or further away from the sensor to fine tune infinity focus. On some adapters this will mean potentially it may clash against…