Run the cable along the bar, cabling the other lanterns as you go. Tape any cable that sags between the lanterns. Do not coil the cable around the bar. Focusing Focusing is easiest with three or four people. Bring the next lantern up before fading the previous one.
Total blackout is dangerous.
The focuser needs a shifter for lanterns which are stuck. Try not to be violent. A lantern should be spotted down so that you can see the centre of the beam clearly. Facing away from the light, give clear instructions to the focuser. Once the lantern is in place, it should be firmly locked off.