What is complete darkness like?

This may seem to be a strange idea, but how many of us have actually experienced complete darkness? For most people, there has always been some light even if it is too low to actually see much. When I was in college, I worked as a photo printing technician. The machine consisted of a track way that moved the continuous paper roll of exposures up and down through the processing chemicals. With the concentrations just right and the movement of the track way timed, the prints turned out perfectly developed every time. There were at most three lines of prints running through the machine at any one time. My job was to take reels of exposed paper and attach them to the end of a reel that was almost done being drawn into the machine. This way the processing was continuous 24 hours a day, seven days a week. Only the technician and the number of lines changed. Since the paper could not be exposed to any light at all before it had been through the developer and fixer, the first segment of the machine was in total darkness. This included the room where I attached new reels and used "Y"s to go up or down in the number of lines. You had to learn how to operate the equipment in total darkness. The room was small, but it felt as if the walls were an infinite distance away. There is no real sense of distance without sight or sound. There was no sense of time. I could work in that tiny room for hours, and it would seem like only minutes. The only measure of time was the eternal hunger of the machine for more paper to process. It never sped up. It never slowed down. If you lost a line, it was gone. You would have to start a new one by attaching a "Y" to another line. I worked the night shift.