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Underwater Photography in UK Waters
with Compact Cameras
Underwater compact cameras can take outstanding underwater photographs in UK waters. From basking sharks, to seals, to wrecks, kelp forests and vibrantly coloured corals and sponges, British waters are rich in subjects for the underwater photographer. But it is much more challenging than working in clear conditions. And there's very little you can expect to accomplish without investing in an underwater flash unit and additional underwater lenses. The three big problems that need to be overcome are low visibility, reduced light levels and a strong and unappealing green cast. The answers to these problems are only to be found in using the right underwater camera equipment.
Without solving the low visibility problem, you are onto a loser. Your underwater photographs will be lacklustre and disinteresting. The visibility is made so poor in UK because the water holds all kinds of matter in suspension. Everything from particles of sand to plankton literally obliterates your cameras view of your subject. They also reduce light levels and destroy contrast. So you need to reduce the particles to an absolute minimum. The only way to do this is to get really, really close to your subject. The maximum range you can take clean underwater photographs over is only about quarter of the distance you can see yourself.
One method is to shoot only close ups, literally choosing tiny subjects only a few centimetres away from your underwater compact camera. Most compact cameras can handle this using their built in flash. There are some technical and philosophical issues to consider, though. Most underwater compact cameras don't photograph small subjects very well. Although they have a built in macro or close up option, it often can't fill the frame with a small subject like a jewel anenome. So it still looks very small in the finished picture. You may be able to overcome this problem by using an add on INON underwater close up lens. This works much like a magnifying glass. So small subjects look much larger and have much more impact in your photographs. Many compact underwater cameras also have a built in flash that cannot properly light one corner of your photograph when shooting close up, creating a harsh shadow in one edge of the picture. Besides, it is very limiting to only be able to photograph small subjects less than 0.3 metre/1ft away from your camera all the time. It's also very boring for your buddy who must follow you around as you slowly search out tiny critters. On the plus side, even if visibility is appallingly bad, you can still have a rewarding photographic dive when a normal diver would be quick to call it a day!
If you want to photograph larger subjects, you'll need to overcome another problem: Lighting your subject. The reason you can only use a built in compact cameras flashgun at very short distances in UK waters is because the flash is next to the cameras lens. When it fires the flash fires into the particles directly ahead of your camera and reflects off these directly back into your lens. The further away your subject is the more power the flash puts out. This lights the particles close to the camera so strongly they overexpose, creating hot spots. Because they are so close to your camera and your camera is focused on something in the distance, the particles are also out of focus making them appear much larger. The result is the underwater compact camera users worst nightmare - backscatter. Backscatter makes it difficult to even see the subject you were trying to photograph. Backscatter from built in flashguns is a major problem even in clear water found in the tropics.
There are a couple of ways to deal with the backscatter problem. One is to avoid using an underwater flash altogether and use only natural light. This brings its own advantages and disadvantages. The advantages include your camera remains easy to use - you can put the exposure on auto, for example - and you don't have to control an underwater flash unit. You can use motordrive, making fish photography easier. You have a very compact system, as you don't need a long strobe arm. The cons are you need to shoot only in the open. Working inside wrecks or trying to photograph critters under dark overhangs isn't going to yield good photos. If you shoot towards the surface, you'll probably be largely restricted to shooting silhouettes. And there's likely to be an overpowering green cast covering your main subject in any underwater photographs taken deeper than five metres or so. You may be able to reduce the colour cast by using your cameras manual white balance control, especially if you also add on an Alex Mustard Magic Filter or UR Pro green water filter. But, ultimately, there are practical depth limits to how deep you can use these colour correction techniques. And, using filters costs you light. Filters work by absorbing colours, rather than adding them. Which means they also absorb light. This brings in another problem of shooting only by sunlight. Very little of it reaches beyond the shallows in the UK. So you may have to increase the ISO or sensitivity of your compact cameras sensor to take pictures. This leads to noise, which shows up as irritating red specks on your underwater photographs.
An underwater flashgun, also called an underwater strobe, is used by most underwater photographers to restore colour and add light to their diving photographs. It also restores contrast, making your subject stand out from the predominantly green background and lets you shoot against the surface light without getting only silhouettes. The flash is positioned off camera and, when aimed properly, will greatly reduce or even eliminate backscatter in poor visibility. INON underwater strobes, such as the INON D -2000 and INON Z-240 offer ease of use, lots of automation with creative manual overides, plenty of power, excellent wide - angle coverage, fast recyling, built in modelling lights and controls that can be operated even when wearing gloves. Using an underwater strobe actually always creates backscatter somewhere. The trick is to aim the strobe so the camera does not see it, yet your subject is evenly and cleanly lit. Key to proper aiming is a long underwater strobe arm. Long underwater strobe arms let you shoot clean images over longer distances. Short arms, often packaged with cheaper underwater strobes become ineffective as the distance between strobe and subject increases. Ocean Optics recommends an overall length of 40 cm or so. Because an arm this long would be difficult to use for close up photography, most experienced underwater photographers will choose an articulated strobe arm that can be folded down for close up work, which you'll likely be doing a lot of in UK waters and extended for longer distance and wide - angle underwater photography. INON underwater strobe arms meet these needs, are easy to position and are available in special INON float arm versions which offset the negative weight of your camera, making handling underwater very much easier as well as safer.
An underwater strobe can restore vibrant colours regardless of depth, but only over a short range. This could be as little as a metre to a metre and a half in low visibility. This leads to another problem and another solution. How to shoot larger subjects, like fellow divers or wreckage. Since we can't back away as we might on land, because of restricted visibility, we have to use a wide-angle lens. And in UK diving conditions, the golden rule is the wider the better. Although much is made by some compact camera manufacturers of built in wide - angle lenses, these usually fall far short of the needs of an underwater photographer working in UK waters. To be effective we need to use an add on wide -angle lens. This enables us to take colourful, high contrast images of larger subjects while remaining within the limited range of our underwater flashunit. INON offer the INON UWL100 and INON Dome Unit super wide - angle lens for some underwater cameras with M67 filter threads. This offers a 130 degree field of view under the water. The INON UWL100M67 underwater lens and INON Dome Unit is not automatically suitable for any housing with M67 filter threads. Check with Ocean Optics for compatibility. The INON UWL100-28AD and INON Dome Unit fits many underwater cameras with built in 28mm lenses. This provides near fisheye underwater coverage of 150 degrees. The INON UFL165AD underwater lens provides 165 degree fisheye coverage for many cameras with built in 35mm lenses. INON underwater wide- angle lenses are true wide- angle lenses that can double or even nearly quadruple your cameras lenses own underwater field of view. They should not be confused with simple dome ports that only restore your built in lenses angle of view so it sees as much underwater as it does in air.
An alternative to a dedicated underwater flash unit is an underwater video light. Normal dive lights, even very high-powered units used in technical diving are often underpowered compared to even a small underwater camera strobe and cause hot spots. High output video lights comparable in power to an underwater strobe need big battery packs if they are to have reasonable duration. This makes them heavy and bulky. Smaller video lights are fine for very close range photography. They are most effective for shooting video clips using the video feature on your compact camera or adding a little foreground "fill" lighting to stills shots, as well as for helping your autofocus to lock on. INON LE Series LED video lights run off just two or three AA batteries and have outputs of 240 to 550 lumens. The beams are designed to provide even, hot spot free lighting. Aluminium bodies and double O ring seals mean they can easily stand up to rugged UK diving conditions.
It is perfectly possible to take stunning underwater photographs in UK waters using underwater compact cameras. What is so often underestimated is the need for equipment that is matched to the conditions and the need for some basic low viz underwater camera skills. Ocean Optics' Mark Koekemoer and Steve Warren are developing INON UK underwater photography courses to help divers take high quality images of their dives in British waters. For more information and advice, please get in touch with them at Ocean Optics.
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