THANK YOU @KeithW! This is exactly what Carl needed to recognize his dock from anywhere in the office. Carl can reliably spot a 3.5inch Augmented Reality University of Cordoba - ArUco 4x4 marker from 10 feet in our night time minimal illumination.
This shows Carl’s view 10 feet away from the ArUco marker at his dock:
(and the temperature jumping up almost to throttling threshold)
It really taxed Carl’s Pi3B to add this video stream to OpenCV for detection at “as fast as possible” - The load reached 5 to 6, meaning he was running at 125 to 150% of processing capacity. I added a short wait to cut the process down to 10 frames a second which brought the load down to 50% of the processor capacity.
Next I need to write the code to drive to the dock and get square to the wall.