Max Ebb — Seeing Red
College students — especially “starving” college students — make the best crew. They are smart, agile, enthusiastic, and best of all, hungry. The problem is, they graduate and move on. Or worse, once they become valuable as crew, they can find a berth on a more competitive boat than my old racer-cruiser. It’s critical to earn their loyalty to the program, and one of my strategies involves their stomachs: We sail across the Bay to an upscale restaurant, my treat. They can bring guests, and that usually brings in more recruits. In terms of speed around the course per dollar spent, it’s a better return than almost any new sail. This year’s preseason crew dinner was particularly promising, with some eager novices and even a couple of talented dinghy sailors at the table.
It was well after sunset when we cast off to sail home. I made sure there was a flashlight attached to each PFD, and put on my favorite headlamp.
“Careful where you aim that thing!” Lee Helm admonished me. She’s only an occasional crew these days, but would never miss a free meal.
“OK, I’ll switch to red,” I said as I changed the color of my headlamp.
“You could use the pirate method!” suggested one of the friends of one of my crew prospects, along for the ride and the dinner.
“Pirate method?” asked another crew prospect.
“AARRH! ‘Tis the real reason pirates wear the eyepatch!” he proclaimed. “Me left eye could be adapted to daylight. Me right eye is in the dark, so it’s dark-adapted. When we storm our prize with cutlasses drawn and chase the crew below, we take off the eyepatch and can see in the dark lower decks.”
“That won’t answer,” replied another crew prospect, who just happened to be a student of ophthalmology. “The range of light intensity in human vision, from lowest perceivable to highest tolerable light level, is about 10 to the 14th, in terms of candela per square meter. And that’s many orders of magnitude beyond what the pupil size can adjust to.
The primary factor for night vision is the buildup of rhodopsin in the retina, increasing light sensitivity in the rods by many orders of magnitude. Pupil dilation is only about a hundredth of a percent of the low light adaptation.”
“But rhodopsin is not circulating in the blood,” said the guest that the ophthalmology student had brought. “It’s local to the retina, so the adaptation could, at least in theory, be eye-specific.”
“But no eyepatch will be that effective,” argued the first scientist. “And do you really want to board a strange ship, ready for a sword fight, with depth perception impaired?”
“AAARRH, me likes the concept anyway,” said the would-be pirate.