Our microscope couplings have individual X-Y centering and Z focussing control on all LED and light guide input ports.  For critical applications where it is vital that the light leaving the coupling is completely on-axis, or needs to be translated (e.g. a moving spot for photolysis) we can also add a tip / tilt control to the mirror cube. This is the same mechanism that we use for pixel alignment of two cameras in our TwinCam and can be fitted to any reflected port.