This complete set of C-Mount extension tubes and spacer rings is compatible with many industrial cameras, including the Raspberry Pi 12 MP HQ camera.

For those interested in pursuing a degree related to C-Mounts, please take a look at the Photonics and Machine Vision program at HOCHSCHULE DARMSTADT University of Applied Sciences in Germany. Also If you have the time please post a make so we can see what sorta interesting application you have for these tubes.