C and CS mounts

[Mavrik 0]

I'm a bit confused what C and CS mounts mean. Is it flange focal distance or thread or no thread difference?

 

I have two different cameras that the manuals says they are CS mounts I swap the threaded lens (no rings) and neither camera will focus. It seems these should be fully interchangeable.

 

I also want to buy some auto iris lenses, but it's not clear what mount I need. The manuals say CS and the camera body is threaded.

[Soundy 1]

http://en.wikipedia.org/wiki/C_mount#CS_mount

[the toss 0]

It is determined by the flange to sensor spacing. A "C" type lens can be used on a "CS" camera by using a spacer ring to correct the focal length. A "CS" type lens cannot be used on a "C" type camera because the focal length will need to be decreased which cannot be achieved short of savage butchery with a file / angle grinder

[Soundy 1]

It is determined by the flange to sensor spacing. A "C" type lens can be used on a "CS" camera by using a spacer ring to correct the focal length.

Actually, it's more important to use the spacer so the back end of the lens doesn't contact the sensor.

 

A "CS" type lens cannot be used on a "C" type camera because the focal length will need to be decreased which cannot be achieved short of savage butchery with a file / angle grinder

Not necessarily true. A varifocal lens can usually still be focused, although likely not through the same zoom range (ie. it may not focus when fully zoomed in or out). Also, many cameras have adjustable back-focus and can be adjusted to a point between C and CS distances, and sometimes beyond them.