Long Jump: Nikon D100 + 105mm f/2.8D AF Micro (with +4 close-up filter), ISO 200, 1/180th at f/38, photo lit by two Subtronic Alpha underwater flash units. Says Mustard: "The diminutive Pygmy Seahorse is about 1cm long, but is regularly photographed by my peers. In an attempt to create a more original image, I dived with the intention of shooting for this composite image of 4 shots of the same individual. This was one of those rare occasions where the wildlife actually did exactly what I had hoped. I had created a low resolution version of this image within 30 minutes of surfacing from the dive." (Photo by Alex Mustard)
A typical underwater shot consists of a flash-lit subject against the ambient-lit background blue of the ocean. Mustard meters those ambient backgrounds with the D2X's matrix meter and tends to underexpose them by one-third to two-thirds of a stop. "Digital cameras have a tendency to run to cyan a bit," he says, "and the underexposure tends to richen up the blues, particularly the light blues."
The D2X's overall color and tonality are very nice, Mustard says, but if you give the subject too much light the camera "has a tendency, particularly in Color Mode III JPEGs, to slightly oversaturate some of the colors. You can get to the point where the saturation is starting to cut into the detail. But that's not so much a problem in RAW."
His genre of photography inevitably slants Mustard's take on his camera's design. "I think the D2X is a lovely camera to handle, but I never get to handle it," he says. "It's my housing ergonomics that are important to me." He's been using housings from Subal, a high-end manufacturer that's especially popular in Europe, since buying his first serious SLR, a Nikon F100. The ND2 model that Subal builds for the D2X and D2H allows Mustard to efficiently access nearly all of his camera's functions, including the many menu settings, while underwater. Most dealers don't publish this housing's price, but it appears to sell for US$4,500 or more, depending on region and dealer.
Besides good ergonomics, other qualities that Mustard looks for in a housing are high build quality and a good selection of quality optical ports. He is also at pains to stress the importance of buying a housing that is well supported by a dealer near you, which is not a given with the relatively small companies serving this niche market. Mustard's Subal dealer is Ocean Optics in London. In "humid, salty, wet environments, you're always going to encounter some sorts of gremlins," he says. If he discovers a problem with his housing shortly before leaving on a dive trip he "can go to London, an hour's drive, and the guy can take it in the back room and fix it. I don't have to ship it halfway across the world and back."
D2X in the House: Mustard's Nikon D2X inside a Subal ND2 underwater housing. (Photo courtesy of uwpmag.com)
Unless specifically trying to shoot with available light only, Mustard dives with two Subtronic Alpha underwater flashes, or 'flashguns' as they're known in Britain. They are mounted on arms from Ultralite Control Systems. Exposure is handled manually by adjusting aperture or, more often, power output for the given subject distance. This is easy to do on the fly because the large majority of underwater photographs are done at a small set of standard camera-to-subject distances. The correct settings are easy to memorize, Mustard explains. And they can, of course, be checked on the LCD and refined if necessary.
Mustard runs 4GB 80X Lexar CompactFlash cards in his D2X. Digital cameras brought to underwater photography the revolutionary ability to shoot many more than 36 exposures on a dive–film, obviously, cannot be changed underwater–but this newfound shooting freedom is constrained by the fact that a long dive lasts 90 minutes and most are significantly shorter than that. So four gigabytes is normally plenty of card capacity.
On the dive boat, Mustard uses Nikon View 6 to download images to an Apple PowerBook G4/1.33GHz laptop using a USB connection between camera and computer. He backs the images up on an 80GB LaCie external FireWire hard drive every night, and every couple of days he makes an additional backup to his iPod, which slowly gets emptied of music to make room for pictures. Because his pictures are not news, he says, "there's no ticking clock. My main goal when I'm in the field is to make sure all those pictures get backed up and get home safely."
On a dive trip, he'll shoot about 40 gigabytes of images a week. "I get a very limited amount of time underwater," he explains, "so when I'm in the field I want to shoot a lot." Though he does no post-processing on location, he can discard many pictures after a quick review on the PowerBook. "In underwater photography, you do have a lot of technical problems, where you can delete images for technical reasons. It's quite easy to chuck away a third of the images from a dive."
It's undoubtedly silly, but it's also tempting, to look at Mustard as a case study in the tensions between, or perhaps in the synthesis of, art and science. Getting his PhD and doing research were the main focus of his efforts through most of his twenties, and his leave from the National Oceanography Centre was intended, in part, to free him up for some independent marine biology research projects he had in mind.
"But I've ended up doing a lot more photography in that year since leaving and really now see myself as a photographer," he says. "It by no means describes everything I do, [but] I would say underwater photographer is my job title." Art, at least for now, may be winning out.
And that may be in part because Mustard believes that digital cameras, which are just recently seeing widespread serious use underwater, offer tremendous new opportunities to shooters like him. "This is a very exciting time to be an underwater photographer," he says. Digital SLR cameras allow them "to be able to create new types of images. And for any photographer that must be the most exciting news you can ever hear."
Zoom, Zoom: Nikon D100 + 10.5mm f/2.8G ED AF DX Fisheye, ISO 200, 1/90th at f/8, photo lit by Subtronic Alpha underwater flash units. Zoom blur was added in Photoshop. (Photo by Alex Mustard)
Aura: Nikon D2X + 10.5mm f/2.8G ED AF DX Fisheye, ISO 100, 1/750th at f/8. (Photo by Alex Mustard)
Going Up: Nikon D2X + 10.5mm f/2.8G ED AF DX Fisheye, ISO 100, 1/60th at f/8. Says Mustard: "The 11 point AF on the D2X is excellent for generating interesting compositions with moving subjects, such as this freediver returning from a dive." (Photo by Alex Mustard)
The new possibilities that Mustard has explored derive primarily from the aforementioned ability to shoot more than 36 pictures per dive and two other characteristics of digital cameras: their playback LCDs and the extensive adjustment of white balance that is possible during RAW conversion.
"Underwater photographers shoot primarily with flashguns," Mustard explains, "so we're working with a light source that, previously [on film], we could never see." And unlike on land, Polaroid proofs were never an option underwater. "With the constant feedback from the LCD screen you can become very creative and very precise with that lighting. [For example], shooting big wide-angle shots at night where you're trying to light up a whole reef with flashguns. [On film] you'd always find that some bits were too hot, some bits didn't have enough light and therefore had gone a bit too blue." If you're shooting close to the seabed "white coral sand very easily burns out," he continues, giving another example, "[so] I often wrap my hand over the bottom of my lower flashgun [to mask off the light]." With the feedback from the LCD "you can try all sorts of things to get the lighting just right."
Other difficult shots he cites are long exposures with subject motion blur and fast-moving fish that are hard to capture in the frame. Because getting time underwater is so expensive and logistically demanding, few photographers would risk any of their 36 film exposures on subjects with such low success rates. For example, in the past "you tended to see motion blur pictures [only] in the National Geographic shoots," Mustard says. "Those photographers had such amazing backup and resources in the field, and they were some of the few photographers who could waste the film, basically." Now, with more shots to play with per dive and instant visual feedback, "those techniques have become available to someone who's only got five minutes to spare on a scuba dive."
The powerful control of white balance afforded by RAW shooting addresses the second most serious obstacle to shooting underwater (the first being keeping seawater and your $5,000 camera firmly separated). Water is an extremely effective blue filter. By the time light has traveled two or three feet through seawater it's lost most of its red wavelengths. By twenty or thirty feet most of the orange and yellow is gone, too. "A lot of new photographers are shocked by how blue it really is," Mustard says.
The filtration effect is sharply variable not only by distance–light becomes noticeably more blue with each additional foot of depth–but also by several other factors such as the water's salinity and the type and quantity of micro-organisms in it. Film photographers who wanted to shoot with available sunlight could attempt to restore color underwater by using red or magenta filters on their lenses and restricting themselves to the precise depth at which the filter would theoretically provide accurate color. But this, says Mustard, "is a hit or miss affair, and mostly a miss affair." Even if you scan your film, any significant color balance errors can't be corrected without noticeable image quality loss.
The only real solution has been flash, and this is why the vast majority of underwater color pictures are lit with them. They produce good color at depth, but you're restricted to very short camera-to-subject distances and relatively small subjects; the flashes simply can't be made powerful enough, at reasonable sizes, to light large objects at significant distances through the strong light-attenuating and color-altering medium of seawater.
But the white balance control of RAW changes the equation. "It enables photographers to bend one of the classic rules of underwater photography, or perhaps even break it completely," Mustard says. With this technique, Mustard uses a red filter on his lens but dives and photographs over a reasonably broad range of depths down to about 45 feet. His color balance is never perfect, but he can easily correct it with the white balance control available in the RAW conversion process. "You're using a filter that's doing most of the work," he explains, "and then you're using the [RAW conversion] to fine-tune that.
"It allows you to photograph large subjects that you could never light with underwater flashguns. Shipwrecks, for example. Now you can shoot a shipwreck and show color over the whole wreck."
After much experimentation, the photographer even developed his own filter for underwater available light photography with RAW image files, called the Magic Filter, which he began offering for sale in August 2005.
It's Magic: Left frame is from film, right frame is from Nikon D2X + 10.5mm f/2.8G ED AF DX Fisheye, ISO 200, 1/40th at f/7.1. Says Mustard: "The picture on the left, of the Wreck of the Giannis D, was taken on slide film, the picture on the right was taken with the D2X and a Magic Filter (plus a white balance adjustment). I hope this gives a demonstration of what a difference digital has made to underwater photography!" (Photos by Alex Mustard)