How Ryo Minemizu captures the hidden wonders of the ocean at night
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Larval smooth angler fish. Photo: Ryo Minemizu |
Underwater photography is a challenging genre to tackle. But the complexity is significantly amplified when you add subjects that are only a few millimeters large, and pitch-black nighttime conditions. Yet that's exactly what photographer and diver Ryo Minemizu is doing with his nighttime dives, also called blackwater dives. Minemizu took the time to answer some questions while on a sailboat in the Pacific Ocean, providing insight into how he captures incredibly unique creatures in the ocean.
When Minemizu started taking photographs while diving, he simply wanted to capture beautiful underwater landscapes and life forms easily visible to the naked eye. Eventually, though, he became more interested in what wasn't obvious, seeking out things that were often overlooked and fleeting moments that didn't get attention. "I was drawn not only to their beauty, but also to the strength and skill required for survival, and the deep significance of life itself," he said.
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Polka dot ribbon fish. Photo: Ryo Minemizu |
To find those fleeting moments, Minemizu has to dive in locations and times when most aren't venturing into the sea. Night dives opened up a new perspective, allowing him to capture creatures in, quite literally, new light. Minemizu also decided to focus on creatures that don't typically get attention. But that makes for tricky photographic scenarios. "Blackwater dive photography is arguably one of the most challenging and relatively new frontiers in the world of underwater macro photography," he said.
"Blackwater dive photography is arguably one of the most challenging and relatively new frontiers in the world of underwater macro photography"
The dark conditions are perhaps the most obvious challenge. Minemizu says that for blackwater dives, a rope with multiple lights attached is suspended beneath a buoy, but its main purpose is safety-related, not for photography. In fact, "lights suspended from the buoy should be as dim as possible to avoid any negative impact on the natural environment," he explains. Instead, he said that divers mainly search for subjects in complete darkness, only using handheld underwater lights as they find them.
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A string of lights hangs from a buoy, but only for safety reasons. Photo: Ryo Minemizu |
When it is time to light up a subject, Minemizu relies on five lights: two Marelux Apollo III 2.0 strobes for ultra-high-speed flash photography, two RGBlue (Super Natural Color) lights with high color rendering for use as target lights and for video recording in the dark ocean, and one INON LE-250 light used to illuminate subjects that exhibit phototaxis (when an organism moves in response to light). He uses the maximum flash sync speed to freeze movement, since the tiny creatures are constantly in motion. But it's not a set it and forget it situation. "Both the exposure and flash intensity are manually adjusted on site to suit the transparency of each subject," he explains.
While light is necessary in pitch-dark conditions, it can also have negative impacts. "Each subject has its own unique characteristics and behaviors," Minemizu explained. "For example, some would close their fins and begin to swim away the moment a light is pointed at them or quickly vanish into the darkness." As a result, he has to anticipate the subject's next move, rapidly assess how it will react to light and how it might behave, and make on-the-spot decisions about lighting. "This involves choosing the right color tone, the best angle for illumination and the appropriate light intensity," he said.
The size of his subjects is another significant challenge. Minemizu is primarily focused on photographing plankton, fish larvae and other minuscule creatures that only measure a few millimeters to a few centimeters. To show them at a large enough scale, Minemizu has to get very close to them. But the water between the lens and the subject adds more complexity. "Even small currents created during movement can disturb the subject’s posture, especially when operating near the minimum focusing distance," he explained.
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Zoea larva of the scarlet shrimp. Photo: Ryo Minemizu |
The constant motion also makes it difficult to find and track subjects. "One of the most important tasks is to find the subject through the viewfinder and keep track of it without losing sight," Minemizu said. To help with that, he explains that a standard macro lens with a shorter focal length (around a 50 to 60mm equiv lens) is more effective than longer lenses. Focus is also a unique challenge. Keeping an animal's eye in focus while it moves around on dry land can be difficult, but imagine keeping that critical focus on a tiny subject floating around in the dark while underwater. After all, both Minemizu and the subject are moving in the current, so he only gets a brief window to engage.
Naturally, there's the gear component to consider as well. Minemizu uses Nauticam housing and the Canon EOS R5 with the EF-EOS R converter. For lenses, he sticks with the EF-S 35mm F2.8 Macro IS STM and EF-S 60mm F2.8 Macro USM lenses. He's opted for APS-C lenses because the equivalent focal lengths are ideal for his subject matter, especially the 35mm lens. He says he's eagerly awaiting an "RF-mount standard macro lens that fully takes advantage of a full-frame sensor’s capabilities," however.
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Minemizu's setup weighs 14kg (31lbs), but is perfectly balanced for working underwater. Photo: Ryo Minemizu |
Minemizu says that on land, his setup weighs 14 kilograms (about 31 pounds). To manage that heft underwater, he adjusts the balance and weight using float arms so the camera is perfectly level and neutrally buoyant, meaning it isn't sinking or floating. Those float arms are attached to the top and bottom, making it easier to rotate the camera vertically.
Beyond all the technical challenges, blackwater dives introduce physical risk. For safety reasons, Minemizu says he limits his dives to 25 meters (82') at night, though most are between 10 and 20 meters (32.8 to 65.6'). Occasionally, the subject he's photographing will begin to descend to deeper water, and he'll need to decide whether to follow or not. "Following it too far can become dangerous," he said. "In such cases, I need to maintain discipline and accept that there are moments I must let go."
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Larval margined flying fish. Photo: Ryo Minemizu |
While Minemizu's images are beautiful, they also contribute to science. Some of the subjects he's photographed are entirely new scientific observations. "In order to recognize such cases on the spot, it is essential for me to have a broad knowledge of plankton, acquired through my own study," said Minemizu. He is working in collaboration with scientists from the Smithsonian Institution and conducting joint studies with universities and specialists studying jellyfish, cephalopod larvae, crustacean larvae and the larvae of various other invertebrates.
You can see more of Minemizu's incredible images on his website.