Image by Elena Kalis
Of all the different types of photography, taking pictures underwater is one of the most difficult. Photography itself is difficult enough, as you must contend with achieving correct exposure, accurate focus, controlling subject movement, attaining pleasing color balance, and dealing with varying light levels. More often than not, the image you saw in the viewfinder only vaguely resembles the final image.
When you also cross the line from photographing in the “air” environment to that of the “water” world, it becomes even more difficult. The line that divides the wet and dry environments brings with it a whole new set of parameters that affect your picture. This is why underwater photographers are a rare breed.
THE CHALLENGES
Light Loss. Let’s explore a couple of the challenges involved in underwater photography, starting with light itself. When sunlight passes through the surface of water, much of it is reflected back upwards, thus the amount of light that continues underwater is reduced. The lower the sun is in the sky, the more light is reflected off the water’s surface. In order to achieve the maximum light level for your underwater photography, the best shooting times are between 10AM and 2PM. As you descend below the waves into the abyss, the light level decreases at an exponential rate. Even at a depth of 100 feet, the light is at an extremely low level.
In addition to this problem, the colors that make up the spectrum of light decrease at varying rates. Red is lost first, and disappears in as little as 15 feet. It’s closely followed by orange, yellow, green, and finally blue. This imbalance in the color spectrum causes havoc with images taken underwater using available light. That is why so many underwater images are taken using electronic flash. Even when a photographer uses a large flash, though, the color and intensity of the flash fall off drastically with distance. Usually, the strobe’s impact dissipates if the flash-to-subject distance is more than eight feet.
In addition to the loss of color and intensity, there is also a contrast and color-saturation loss as the subject’s distance increases from the camera and flash.
Backscatter. If all of that were not discouraging enough, the underwater world also has its own unique problem. As particulate matter floats through the water with the currents, it takes on the appearance of snow in a snowstorm when illuminated by a flash or other bright light source. This unique effect is called backscatter and is one of the biggest issues plaguing underwater photographers.
Water Temperature. The temperature of the water itself can add to the difficulty of taking pictures underwater. Water temperatures can range from a comfortable 85 degrees Fahrenheit to a freezing 33 degrees. As the water becomes colder, the photographer must wear heavier wet suits to combat the cold. As these wet suits increase in thickness, you must add even more lead weight to counterbalance the buoyancy of the suit. Then you must wear gloves to stay warm, but these make camera adjustments very cumbersome. While the popular dry suits offer another choice when cold-water diving, they still restrict your ability to take pictures underwater.
Currents. Are you beginning to get discouraged from underwater photography? Wait, we’re not done yet! Many of the best diving locations in the world can have mild to strong currents that make it difficult for you to remain stationary long enough to take your picture. With the new environmental concerns about getting too close to the reef, photography in currents becomes very difficult at best. Even when the currents aren’t running, the larger camera systems are bulky and can often cause drag as you maneuver through water.
Humidity and Corrosion. The salt air and humidity are other parts of the equation working against you. Salt water is very corrosive, and can quickly damage both film and digital cameras if even just a couple of drops get in the wrong place. Most tropical climates have high humidity which gets trapped inside the camera housing as you make your dive. As the camera batteries heat up, moisture forms small clouds inside your camera housing.
SO . . . WHY BOTHER?!
Whew! With all of these environmental factors against you, why would anyone go to the trouble and expense of taking pictures underwater? The answer is apparent the first time you come face to face with a 40-ton humpback whale, or a tiny timid seahorse seeking camouflage in the soft coral. Or, it might be the intrigue and challenge of the cuttlefish that changes shape and color just to escape capture by the underwater camera. All underwater photographers are fascinated with the awe and mystery of the underwater world and long to share their experiences with family and friends—even the entire world.
