In the past, it was not unusual that the captain gave the order to kill all the lights at the front and front quoaters of the ship.
It was indeed done for navigational reasons not to be mistaken for anything els but a ship, the officers on board kept a good watch inside the ship to be sure the curtans or blinds were closed, and stayed that way until the captain desided otherwise.
The more traffic they encountered the more these procedures were issued.
These days there is still a regulation about these procedures, although with modern navigational instruments you have a better view of whats around you (radar+ais+vhf) nevertheless, i still hear occasionally of Captains to order a "lights out"