Hello Mu-43 community, I recently just purchased a C mount type lens.It is a Cosmicar 25mm 1.9. I also purchased an adapter seperately for my olympus omd-em5. However I noticed that the lens doesn't fit adapter's radius. So my real questions of concern are, did I purchase a wrong C mount lens? Is it common for users to sand down or bore out the adapter radius to fit the lens? I thought C mount lenses would fit C mount adapters?