Some of the best underwater photos of all time are, arguably, silhouette shots. Wrecks, other divers, and most types of marine life lend themselves beautifully to becoming creative photographic expressions. While you might think there's not a lot to capturing perfect silhouettes, and while getting good silhouette shots can be easy, there are some techniques that will allow you to take truly impressive photos as compared with photos that are merely good. Let’s take a closer look.
Backlighting and Background
Creating silhouette photos underwater requires good backlighting for clear, crisp shots in most cases, although there are times when a more mysterious look is desirable. Don't let poor backlighting conditions stop you from attempting to capture shots you think might be interesting. Any object with a strong shape or a shape that is easily recognized usually makes for a great silhouette photo!
Some of the best underwater silhouette photos feature interesting details in the background; for instance, divers' bubbles, sunbursts, and ripples on the surface can all add texture and depth to silhouette photos. Spend a little time viewing silhouette photos to see all the different ways photographers have captured background features.
Foreground
You can add even more interest to your silhouette shots by allowing a little foreground to show - corals, wreck structures, pilings, or other strong elements add depth. When composing these photos, remember not to allow much of the foreground to get in the way of your main subject, and keep in mind that all detail in front of the subject will be lost. Keep your shots simple for good effect; even a single fish or another diver, close up with the sun directly behind can make an outstanding impression.
Using Camera Features to Your Advantage
Try using manual exposure mode or bracket your exposures if possible. If incorporating a sunburst or sun ball into your photo, ensure you use a fast shutter speed of 1/150th or higher to freeze the sunrays. Since you won't be using strobes or flash at all to light up the foreground, select your camera's highest setting for the best chance of capturing sharp lines.
If you don't have time to shut off strobes and you want to capture a silhouette, take two shots in rapid succession, one right after another. Your strobes should do a full dump on the first shot, and your second shot should be dark. This is a technique many professionals use while shooting in continuous mode.
As you are studying silhouette photos, you'll notice that the best have a few things in common: the subject is strongly silhouetted and away from the reef or wreck, or it is in blue water. Many of these are divers, manta rays, sharks, turtles, and other large subjects with strong outlines. The silhouettes captured are either black or very close to being black, and there are no colors other than black and blue in the photographs. Don't be afraid to practice photographing underwater silhouettes every chance you get. Even if all you have is a basic point and shoot, you can get some great photos just by working with backlighting and looking for interesting compositions.