Anyone who’s tried to photograph falling snow with their high beams on knows how that turns out. You get a wall of glare and hardly any snowflakes, because the light bounces off everything at once and there’s nothing left for the camera to pick out. Now move that same problem into the black water off Monterey, onto a camera bolted to a 10,500-pound robot, and you’ve got the evening MBARI’s Bioinspiration Lab had on August 20.<\/p>\n
The camera is called EyeRIS, and it’s a fairly serious piece of hardware. One sensor, with 36,000 microlenses stacked in front of it, every one of them looking at the same spot from a slightly different angle. Think of an insect’s eye, and you’re close enough. That’s how it builds 3D video of animals that would come apart if you tried to net them, and it’s the camera behind MBARI’s Nature paper on how deep-sea octopus swim<\/a>. For this trip it was bolted to the remotely operated vehicle Doc Ricketts<\/em>.<\/p>\n What the team wanted that day was the flow around a deep-sea coral. Not the coral itself. The stuff drifting past it: plankton, marine snow, the specks a coral actually eats. EyeRIS carries its own array of six lights, and all six were doing a beautiful job of lighting the coral and the seafloor behind it. The particles vanished into the glare.<\/p>\n So why not switch a few of the lights off?<\/p>\n Because that just gets you a dimmer version of the same washed-out frame. What they needed was the opposite of less light: a small amount of it landing on one small piece of water, with everything around that piece left dark.<\/p>\n If you know one thing about the deep-sea anglerfish, it’s the glowing lure it dangles in front of its own face. That light isn’t there to illuminate the neighborhood. It’s a single bright point in an otherwise black ocean, parked exactly where the fish wants other animals to show up. It’s a pretty efficient way to spend photons when you live somewhere the sun never reaches. The team copied the trick and nicknamed the rig the Anglerfish.<\/p>\n Building it took one evening and nothing that wasn’t already on the ship. Senior Research Engineer Joost Daniels and the rest of the lab unbolted the light arms from the sides of EyeRIS, joined them end to end into one long boom, and hung two lights off the tip. A hydraulic system that was already there to tilt the old light array got co-opted to swing the boom around. Then they wrapped rubber strips around both lamps as a shroud, so the beam falls on the water they care about instead of everything else in frame.<\/p>\n The rubber strips are frankly my favorite part of this. Here’s a vehicle rated to 13,123 feet, carrying a camera with 36,000 lenses in it, and what made the science work was a longer stick and some rubber cut to shape at sea.<\/p>\n They dove with it on August 21. Daniels wrote in his expedition log for MBARI<\/a> that the boom is “floppy like an anglerfish’s lure”, which reads like a complaint and isn’t one. They’d been worried about exactly that, because a long boom that sways and won’t hold still is no good to a camera measuring how fast particles move. It swayed. It worked anyway. Daniels says these improvised shipboard rigs normally fail fast and are worth building for what the failure teaches you, and that this one didn’t do him the favor of failing.<\/p>\n A couple of things he doesn’t give you. There’s no length for the boom anywhere in the log, and no depth for that dive. The expedition worked two sites, Monterey Canyon and Sur Ridge, and as far as I can tell the log doesn’t say which of them the coral was sitting on.<\/p>\n Doc Ricketts<\/em> is 12 feet long, 6 feet wide and 7 feet tall, and MBARI’s spec sheet for the vehicle<\/a> puts it at 10,500 pounds. It’s electro-hydraulic, it’s rated to 13,123 feet (4,000 meters), and it’ll carry another 606 pounds of science gear in the water on top of its standard tool sleds. It passed its 1,500th dive this summer.<\/p>\n It’s also not a drone, whatever you call it in conversation. There are pilots sitting in a dark control room on the ship flying it down a tether, and Mark Talkovic, the chief ROV pilot, was one of them on this trip. That makes it a different animal from the 88-pound float that sinks 19,700 feet on its own<\/a> or the seabed drone that lines itself up with its own ship off Nova Scotia<\/a>. Those two have to get through the whole job with nobody to talk to.<\/p>\n Doc Ricketts<\/em> has a cable and a crew. That’s why you can take its lighting apart in one evening and try again the next morning.<\/p>\n A coral doesn’t chase anything. It sits in one place and waits for food to come to it, so how the water moves around a coral is most of the story of whether that coral gets to eat. Measuring flow and feeding on deep-sea corals was one of the stated goals of the Movement in the Deep expedition<\/a>, along with imaging the delicate drifters, the jellies and siphonophores that fall apart the moment you try to collect one.<\/p>\n The Bioinspiration Lab brought six imaging systems out for this one. Two went on the ROV, EyeRIS and a laser scanner called DeepPIV, and four stayed in the ship’s lab for animals brought up to the surface. FathomNet Engagement Coordinator Lilli Carlsen, who wrote the first log of the trip, says the whole lab hadn’t shipped out together on a long expedition in four years, and that the last one was on the old flagship Western Flyer<\/em>. This trip is aboard the David Packard<\/em>, a newer and much bigger ship, and it’s the lab’s first expedition on it.<\/p>\n What I like here is the ratio. You can spend years building a light-field camera, hang it off a vehicle this size and sail the whole thing out on a brand new flagship, and still end up unlocking the science with a longer stick and some rubber strips. That’s not a dig at any of it. It’s arguably the best argument going for putting engineers on the boat instead of leaving them on shore, because nobody builds that fix from a desk in Moss Landing.<\/p>\n MBARI published Daniels’ log on August 21, the same day the Anglerfish made its first dive, and the Movement in the Deep expedition ran through August 24 with Kakani Katija as chief scientist.<\/p>\n","protected":false},"excerpt":{"rendered":" Anyone who’s tried to photograph falling snow with their high beams on knows how that turns out. You get a … <\/p>\nSo what does an anglerfish have to do with a camera?<\/h2>\n
The machine underneath all this isn’t small<\/h2>\n
Why film the water instead of the coral?<\/h2>\n