Since I discussed underwater macro photography in the last column (see Get Up Close and Personal ), this month I want to examine more thoroughly the other main category of underwater shooting: wide-angle image making.
Underwater wide-angle photography can be a little more complicated than macro photography so many amateur shooters shy away from it. That's too bad because this type of photography can produce striking and vibrant images of the undersea realm that have broad appeal even to people in the non-diving world. (Yes, as sad as it sounds, there are non-divers out there who don't know the difference between a harlequin shrimp and a shrimp cocktail). Wide-angle photography allows the photographer to create images with a much greater perspective on large fish, marine mammals, and coral reefscapes, as well as how divers interact with them.
While point-and-shoot digital cameras are still capable of making decent wide-angle images, they tend to be pretty limited in their ability to effectively capture a panoramic view of these subjects. For this reason, I am going to concentrate on wide-angle images produced with housed Single Lens Reflex (or SLR) cameras. Most of the same concepts apply to the point-and-shoot genre, but the results will typically be less impressive. Sorry, point-and-shooters...I'm only the messenger.
Shooting underwater with SLRs requires the user to select from a variety of lenses of different focal lengths, place that lens on the camera, and then insert this equipment combination into a housing made specifically for that camera. Once you make your selection and seal up the housing, you are locked in to this combination until you surface. It is important to do some pre-dive research to learn what you are likely to encounter on each dive so you can select the proper lens. Remember, don't wait until the last minute to choose and then rush to prepare your camera and housing. This can lead to very upsetting problems, including annoying everyone else on the dive boat, and even worse, flooding your rig.
For extreme wide-angle shots, the most commonly used lenses for digital SLRs are Nikon's 10.5mm fisheye and Canon's 15mm fisheye. For more standard wide-angle shots, Nikon's 12-24mm or 17-35mm and Canon's 10-22mm or 17-55mm zooms are most common. The one advantage to these wide-angle zoom lenses is that they give you the ability to pan in or out to frame the image according to your taste. The downside, however, is that they require you to purchase a zoom gear so you can access this function with your housing. They may also require a diopter (basically, a screw-on close-up filter) to allow you to focus properly underwater.
We've all seen those incredible magazine covers showing divers posed next to a reef or shipwreck or interacting with dolphins, sharks, or turtles. In these shots, typically the main subject (the diver, the dolphin, a wall of corals, a school of fish) is bright and colorful while the background is a beautiful, clear ocean blue. Unlike in macro (close-up) photography, which most often relies solely on light from strobes to properly expose the frame, this type of wide-angle imagery requires two light sources: 1) strobes and 2) natural sunlight.
Here's how it works: The blue water background is exposed only by the natural sunlight filtering down from above. The foreground subject (the diver, the animals, the reef) is illuminated by the light from the strobes.
For the sake of simplicity, I suggest that you keep the shutter speed at a constant setting, like 1/60 or 1/80, so the only adjustments you have to make are to the aperture. Fire a few test shots with the strobes turned off, and look at your camera's LCD screen to gauge whether you are capturing the blue the way you want to. You may find that even though your camera's exposure meter says your settings will render a perfectly exposed image, the resulting image is a little brighter than you like. I typically adjust the aperture until my camera's meter says I'm going to slightly underexpose the image.
Note: It is important to remember that the ambient light constantly changes as you change your depth or when clouds pass overhead. Also, the angle of your shot (up toward the surface versus slightly downward) can greatly affect exposure. For this reason, you should check the lighting frequently as your dive progresses.
Once you have dialed the settings to your liking, turn your strobes back on. As I've mentioned in previous columns, most strobes are ineffective from a distance of more than four or five feet from the subject (for more on strobes, see The Lighting Blues ). Therefore, remember to get close enough to the foreground subject to effectively light it with the strobes.
Since you have already dialed in your exposure for the blue water, any changes you make to your aperture or shutter speed now will alter that exposure. Consequently, you may have to make additional adjustments to the strobe power settings to properly expose the foreground subject as well. In clear water when I'm within five feet of my subject, I leave the strobes on half power initially and then make adjustments up or down as necessary. Be mindful of strobe positioning and angle so you can minimize backscatter in the image (for more on backscatter, see Get Up Close and Personal ).
While this process might sound complicated and potentially frustrating, it will eventually become second nature to you. It's not uncommon to find a "sweet spot," where you know almost exactly what combination of strobe power, aperture, and shutter speed settings to use for the shooting conditions.
If the subtle setting combos sound like way too much effort, you can still make some creative and interesting wide-angle images using only ambient light, especially at depths of fifteen feet or less. Even in deeper water, a technique that often produces great results involves being directly below a subject and shooting right up toward the surface to create a silhouette of the subject against a background of blue water. Remember to turn your strobes off for these shots; they won't be effective and will likely illuminate backscatter in the water column that you don't want in your shot.
As always, don't forget to be mindful of your buoyancy, and check on your buddy every so often. Buddy relationships tend to be short and not so sweet if one of you completely ignores the other. Until next time...
Have fun and dive safe,
To view more of Jeff's work, log on to: www.jeffyonover.com .
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Photos by Jeff Yonover (from top): Dive boat moored at healthy reef, Kimbe Bay, Papua New Guinea; Batfishes (Platax teira), West Papua Mar, Indonesia; Diver with soft corals, West Papua Mar, Indonesia; Napoleon Wrasse (Cheilinus undulates), Red Sea, Egypt; Manta ray (Manta birostris), West Papua Mar, Indonesia.