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  • Photographing Sharks

    It’s easy to impress your non-diving friends and neighbours with the photographs you might take of sharks. Shark encounters come in a number of types: Chance encounters such as you might get ocean-roving oceanic white-tip sharks, encounters where currents attract requiem sharks that enjoy surfing on the flow, encounters with bottom feeding sharks such as nurse sharks and leopard sharks that like to lie up and rest during the day, and where sharks are feeding.

    The normal rules of underwater photography apply, in that it’s best to use a wide-angle lens and get as close as possible. Reduce the amount of water between your camera and the subject.

    Oceanic white tip shark Ocea-roving oceannic white tip shark

     

    Ocean roving sharks tend to be close to the surface so it’s quite possible to get reasonable pictures without an underwater strobe or flash but these are ambush predators so designed as to offer a low contrast image to intended prey. A correct flash exposure can give contrast and add drama.

    They tend to swim around 6m deep, constantly investigating anything that might be the source of a meal. That is why they approach divers, often only to turn away at the last moment when they consider us to be animals too big for them to take on. Sharks appear to judge size by height rather than length so if you want a shark to come close, present as small a frontal area as possible by being horizontal in the water. Go vertical and you will almost certainly scare off such a shark.

    Those sharks that lie about during the day such as nurse sharks can be approached with caution so as not to disturb them and you will have time to get more than one exposure adjusting the lighting and exposure to suit. The same can be said of white-tip reef sharks, although these are much more skittish. They lie about on the seabed during the day because they are able to force oxygenated water through their gills without forward motion like most other requiem sharks, but be aware that because they are grey and again designed for ambush, they need careful lighting just the same.

    Scalloped hammerheads at a cleaning station Scalloped hammerheads at a cleaning station

    Then there are the cleaning stations. Find out from the local dive guide which fish are the resident shark cleaners and find where they are aggregating. Then you just need to be patient, keeping as still as possible, waiting for the sharks to approach for a visit to the manicurist. It’s the only way to get pictures of scalloped hammerheads because they are so skittish. You need to sort out your overall exposure so that the background is reproduced an acceptable blue, adjusting the power of the flash (or strobe) to suit the foreground shark.

    When it comes to feeding sharks, things become a lot more frenetic. You need a fast shutter-speed but you will be limited to the fastest speed with which your camera will allow you to synchronise your flash.

    Sharks feed in two distinctly different ways. When chasing live prey they become very agitated and it’s best to keep clear at this time, even exiting the water. Sharks have more senses than we do but it’s a fact that they have a nictitating eyelid that covers their eyes to protect them at the moment of biting so that they virtually do the last part of an attack with their eyes closed. Mistakes can happen. Anyone who has attended a night dive at Manuelita Island near Cocos will attest to the fact, it can be chaotic, and that’s when it’s only little white tip reef sharks start hunting small fished by the light of the divers torches. Bigger sharks can explode with energy when they sense a live prey.

    White tip reef sharks competing for live prey at night. White tip reef sharks competing for live prey at night.

    On the other hand, when sharks sense there is a meal of carrion to be had, they are much more leisurely in their approach. There are no vibrations of injured or dying fish to excite them or ring their dinner bell, just the odour of an easy meal wafting on the ocean currents. So they tend to swim round in an orderly manner.

    Staged shark feeds such as they often do in the Bahamas and some parts of the Caribbean will give any diver witnessing the event that sharks, although impressive beasts, have a pecking order and act in an orderly manner so that they do not risk injuring each other. They still move quite quickly so you will still need to choose the fastest shutter-speed you can, in order to get sharp pictures. If you do not, the flash will record a sharp image but there will also be a less sharp ghost image due to the daylight exposure being too long.

    Using twin flashguns can also be counter-productive because those guys in the grey suits need a bit of contrast to light them up with plenty of shape and contour. It’s one occasion when the single flashgun reigns supreme.

    Caribbean reef shark at a staged shark feed. Caribbean reef shark at a staged shark feed.

    With plenty of sharks attending a staged feed, you won’t be able to judge where any are at a given moment. You’ll need to take a lot of pictures because inevitably one animal will obstruct your view of another, many times when you release your camera’s shutter. If you shoot RAW files, you’ll be able to adjust these after the event and not have to keep adjusting your flashgun’s output to account for sharks being at different distances from the camera.

     

     

     

  • Our Colourful World Underwater

    If you read the last blog about the physics of underwater photography you will understand why everything can look monochromatic underwater, once you have moved away from the surface. This can be misleading and often the new diver’s first introduction to the colour of our underwater world is during his or her first night dive.

    Soft corals in the Maldives (Vilamendhoo).
    Without the blue of the daylight swamping the true colours of the reef, the diver’s underwater light illuminates everything in its true colours – and what a colourful world it is! It’s for this reason that experienced divers are often seen going into the water with powerful lights or torches even on the most brightly lit days. By taking a bright white light close to a subject, it’s revealed in its true kaleidoscope of tints. However, at night you’ll see the fishes in their night-clothes (so to speak) because often the colours they exhibit in daylight are different to those in the dark.
    Coral trout on a sponge encrusted wreck.
    It’s amazing how much marine animal life is actually bright red when you consider that red looks black to most marine life. Nobody can really explain the reasoning but it’s true. Often, fishes that may appear a dirty green colour by natural light are revealed to be bright scarlet in the beam of a lamp. Underwater photographers can take advantage of this phenomenon by lighting up their subjects with an underwater flashgun or strobe light while those shooting live action can employ powerful video lights to the same effect.
    Anemone fish in a purple anemone.
    Even the smallest subjects can be revealed in a startling vividness once they are subjected to a full spectrum of light. Sharks may be the guys in the grey suits, along with many other predatory pelagic species, but once you look closely at any territorial animal with the aid of your diver’s torch, you can appreciate the full range of hues that they wear.
    A wreckfish in the wreck of the Chikusen, BVI.
    Big grouper suddenly appear to be much prettier than their otherwise brutish look might signify.
    Green turtle feeding on seagrass (Egyptian Red Sea)
    Even green turtles can be revealed as more colourful than you would expect. You would not contemplate entering a dark wreck without a lamp to guide your way (and possibly a second one stowed about your person as a back-up should the battery in your primary lamp inexplicably fail). That may seem obvious but even rusty shipwrecks and their cargoes can be quite colourful beyond the range of the oxidising metal because they get encrusted with tiny sponges and hydroids that give them colour. It's a colourful world.
    Inside the Rio de Janeiro Maru, Truk Lagoon.
    As for soft corals, these colonies of animals blossom in a strong current and display themselves in a wide range of reds, oranges, yellows, purples and blues. Going diving on a tropical coral reef without the aid of a lamp is rather like turning down the colour on your television set and watching everything in black-and-white.
    The wreck of the Bianca C in Grenada.
    Get yourself a good diving lamp and a back-up if you are diving at night or in wrecks and if you are shooting pictures, the people in Ocean Leisure Cameras, the store within the store, can fix you up with the appropriate lighting array. Come in and discuss it with them. The store is open seven days each week. Take a suitable light with you when scuba diving  and reveal the colourful underwater world. If you've enjoyed reading these blogs, you will enjoy reading Amazing Diving Stories by the same author.

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