Taking Underwater Photos in Limited Visibility
By Marty Snyderman
I have just moved from south Florida to Seattle, WA. The diving in the Pacific Northwest is spectacular, but on the whole my photographs aren't as good as my opportunities. Any advice?-Greg G., Seattle, WA
No question about it, you need to utilize proper shooting techniques to get great results when shooting in greenish waters where 10- to 20-foot visibility is common. The water quality in places like the Pacific Northwest, California, the Great Lakes and New England make shooting conditions more difficult, but by no means is it impossible to enjoy consistent success. The key is to be more disciplined in the techniques you apply. These techniques will also serve you well in crystal clear waters, but are more important when water conditions are not favorable.
1. Get as close to your subjects as you possibly can. The primary culprit of poor visibility is increased particulate matter suspended in the water column. The less water between your lens and subject, the less particulate matter you shoot through, and the sharper your images will appear. Suspended particles absorb, refract and diffuse light, causing the edges of elements in underwater photographs to blur.
2. Edge light when using strobes. Edge lighting means using the inside portion of the strobe beam to illuminate the subject, while not lighting the area between the lens and subject. In other words, you don't aim the heads of your strobes directly at the subject. This technique lets you avoid illuminating the out-of-focus particles that are positioned between your lens and subject. When illuminated, these particles become what photographers call backscatter.
Edge lighting is especially helpful when using a two-strobe camera system. Mastering edge lighting requires familiarity with the beam pattern and the angle of coverage of your strobes, and requires some practice.
3. Consider shooting at a slightly downward angle to eliminate a black water background when creating macro images. Because you have less ambient light to work with, background water often turns out black, or near black, in your images. Suspended particles are often lightly hued, and they stand out against black water. If you "go against the book" by shooting at a slightly downward angle and framing your subjects against more lightly hued reef or sand, the suspended particles are less likely to appear as unacceptable distractions.
4. Be careful not to stir up the bottom. No matter where you dive, you never want to stir up the bottom, but in cooler water you will require more weight, and learning how to move slowly and deliberately can require additional practice. When you want, or need, to settle onto the bottom to set up a shot, try to plan ahead as you descend so you won't have to swim into position after reaching the sea floor. Instead, try to descend into the desired shooting position, and then move slowly and deliberately as you frame your shot.
5. Power down with your strobe when creating wide-angle images. The idea is to balance the intensity of strobe light with the intensity of sunlight in wide-angle images such as seascapes. In greenish waters you usually have less natural light to work with. In order to avoid overpowering the intensity of natural light with your strobe, and to avoid over exposing your subject, you will want to turn down the power.
Finally, the most important piece of advice I can give is to believe that you can create compelling images in reduced visibility. Self-confidence is perhaps the best technique.
Many point-and-shoot camera systems come with a flash or strobe that is built into the camera body. This applies to popular models such as Sea & Sea's MX-5, Bonica's Sea King Snapper, the Sealife Reefmaster, Ikelite's Aquashot-3e and the Epoque 100 Plus. Using the built-in flash provided on these cameras to maximize image quality requires an understanding of the benefits and limitations of underwater strobes.
As a rule, underwater photographers use a strobe to serve two functions simultaneously. First, a strobe provides light for exposure, and second, it enables the photographer to "paint" colors into strobe-lit foregrounds and foreground subjects. A strobe can add considerable appeal to images that include colorful subjects and foregrounds. As divers, we know that water is a selective filter of the wave spectrum of light. Waves on the red end of the spectrum are filtered out at much shallower depths than waves on the blue end. If used properly, a strobe can help you paint the red, orange and yellow hues into foregrounds and foreground subjects that have been filtered out by the water column.
Getting Started: How to Get What a Strobe Has to Give
It's important to realize that a strobe can only impact the look of objects in the foreground of your photographs. In order for a strobe to add color, you must get close to objects that are in the foreground of your photographs-very close. A strobe, no matter how big, how expensive or how powerful has no impact on the background water color or the appearance of objects in the background.
With some strobes, you might see some impact from as far as eight feet away from your subject. However, the strobes that are built into most point-and-shoot cameras are capable of adding significant color from a maximum distance of about six feet. Even with cameras that provide "automatic" exposure control, you absolutely must get close enough for the strobe to have a chance to do its job. If you are too far away from your subject, colors go flat. You want to use your strobe to help expose and add color to the scene immediately in front of you, not to the Manta Ray or shipwreck in the distance. Distant objects can only be illuminated by natural light. As a rule, you will need to be between two and six feet from your subject in order for the strobe to paint in the rich colors desired in your photographs.
Be aware, too, that the focus on many point-and-shoot style cameras is set to work with subjects that are two to six feet away from the lens. So, if you work within this range, you have the best chance of capturing sharply focused and colorful subjects.
The placement of a strobe in relation to the subject it is lighting also plays an important role in the capturing of an image. We will take a look at where to position external strobes in next month's issue. Until then, remember to enjoy the process of photography, not just the processed image.