used these, and have the controller, its to program at the camera when setting up, most of the time we pointed in the general direction and setup via rs485 pelco d 2400
zoom in/out zooms the camera
the other things are your blc, wdr sharpness, contrast, bright etc, most of the time for general use these wont need changing anyway
all the controller does is allow easier access its an extension of the 5 buttons on the back, does exactly the same thing just on a 30cm lead