I have a "gelded" DR Summicron. About 11 years ago, I had DAG machine down the close-focus cam so it no longer hit the back of my M8. No regrets--I'd rather have a lens I can use than a shelf queen. It's correct that the close focus range no longer works with the RF. But actually, close focus still works with Live View on the later digital M cameras. To unlock the close range, I just push down on the little ball-bearing on the flat top of the mount where the goggles would attach. And of course, I can use the DR with an adapter on a micro-4/3 camera.