How to define a point or line in polyscope?

I am using UR10 mounting a DSLR to shot some video. I want to set a aim point ,and keep the point on the Z axis of tcp during the movement of the robot, i dont konw how to do this on PolyScope, anyone can help me ? Thanks for any assistance!

Look into Remote TCP. See e-Series User Manual Seciton 23.13.