카메라 렌즈 마운트의 종류 – C-마운트, CS-마운트, M12 마운트 (S-마운트)

Choosing the right mount is critical to ensure the lens can focus properly. Frequently asked first questions when building a camera is:

• Will my CS Mount Lens work with my C Camera Mount?
• Will my C Mount Lens work with my CS Camera Mount?
• What is the difference between a S Mount lens and a M12 lens?
• How can I use an M12 lens with a C / CS mount camera?

If you've wondered any of the above, you're in the right place! Below is a concise guide to lens mount compatibility. We'll compare C-mount vs CS-mount lenses and M12 vs C/CS-mount lenses – highlighting key differences, compatibility issues, and use cases.

M12 렌즈 마운트 vs C-마운트 vs CS-마운트 렌즈

M12 lenses (also known as S-mount lenses) are miniature lenses with a 12 mm diameter thread (M12 x 0.5). They are widely used in compact board cameras.

Comparing an M12 lens vs a C-mount lens (or CS-mount) reveals major differences in size and standardization:

Physical Size and Thread: M12 lenses are much smaller. They use a metric M12×0.5 thread instead of the 1″-32 UN thread of C/CS mounts. The entire lens is often only a few centimeters long. This compact size makes M12 lenses ideal for small embedded cameras, but it also means they typically work with smaller image sensors up to about 2/3″ sensor formats.

In contrast, C-mount lenses are larger and can support sensors up to around 1″ or more.

Flange Focal Distance: Unlike C/CS, the M12 mount does not have a standardized flange focal distance. The distance from the lens to the sensor in M12 systems depends on the specific lens design and the lens holder used. Each M12 lens must be matched with a compatible lens mount holder and adjusted (typically by screwing in/out) to focus on the sensor.

Not all M12 lenses are interchangeable across different holders or cameras – you must ensure the mechanical back focal length and lens barrel length suit your camera's mount. In other words, an M12 lens that works in one camera might not focus in another if the lens housing is different.

Mounting and Adaptability: M12 lenses screw into small lens holders on the camera board (often secured with glue or screws once focused). These holders are sometimes called S-mount or board-mount holders. Adapters do exist to use an M12 lens on a C-mount or CS-mount camera. However, compatibility is not guaranteed. In practice, if you attach an M12 lens with an adapter to a C-mount camera, it may not be able to focus to infinity or it might vignette since M12 lenses are designed for smaller sensors.

Always check the lens specifications and, if possible, test the combination before committing to an M12-vs-C/CS swap. In short, M12 vs C-mount/CS-mount lenses trade off flexibility for size and cost.