Yes you can use multiple hand units to control separate motors and of course any INPUT (Large Knob, Side Knob A etc.) can be assigned to any LENS AXIS. However, you must configure the Controllers so that they don't clash. Care must be taken to disable potential conflicting input controls BEFORE powering on the receiver and motors. Failure to do so could result in sporadic motor gear movements that may damage a lens (caused by multiple Controllers fighting for control).
To pre-configure Controllers’ AXIS INPUTS for the above example:
-On the ‘dedicated Focus Controller’, assign OFF for IRIS AXIS
-On the ‘dedicated Iris Controller’, assign OFF for FOCUS AXIS
-On the ‘dedicated Iris Controller’, assign KNB (Large Knob) to IRIS AXIS
For instructions on how to navigate the Controller Menu please refer to page 11 of the MK3.x User Guide.