In the first two columns, I talked about some of the basics for starting your underwater photography career: mastering your dive skills, familiarizing yourself with the fundamentals of photography , and understanding how light, both natural and artificial, behaves underwater . Assuming that you've digested all of the above, let's get up close and personal with underwater macro photography.
All underwater photography can be categorized into two types: (1) wide angle (above left), which we will discuss in the next column, and (2) macro (above right). Back in high school, my economics teacher tried to teach us the difference between microeconomics and macroeconomics. Maybe your teacher did, too, and had as little success as mine did. If you haven't already forgotten that lesson, I'm giving you permission to do so now. After all, who wants to talk about the economy anyway? In underwater photography, the terms macro and micro both refer to the same thing: using a lens designed for close-up photography, and making images of typically small subjects.
Point-and-shoot digital cameras have a fixed, non-removable lens that can be used to zoom in or out to create either wide-angle or macro images. Some point-and-shoots also have a macro or close-up program mode that more easily facilitates macro shooting by using preselected apertures and shutter speeds, and that sometimes allows a closer minimum focus distance.
With housed SLR digital or film cameras, however, the user must decide which lens to attach to the camera, as well as the appropriate corresponding lens port for the housing. In SLR photography, both above and below the surface, the most commonly used macro lenses are Canon's 50mm and 100mm "macro" lenses, and Nikon's 60mm and 105mm "micro" lenses. See what I mean about ignoring your high school econ lessons?
If you want to make macro photography as simple as possible, here's an easy way to start:
Leave your strobe(s) on full power. If your shots are overexposed, move the strobe(s) further away from the subject, use a faster shutter speed, use a smaller aperture, or any combination of the above. If your shots are underexposed, even with your strobe(s) at full power, try getting closer to the subject, using slower shutter speeds (but not so slow the image blurs), and larger apertures.
If the above is still confusing, keep reading for more detailed tips on going small.
Once you have selected the lens you are going to use for a specific dive, have put your rig together, and closed the housing, you are locked into that configuration for the dive. Because of this, I highly recommend that you ask the dive master for some pre-dive information about the types of subjects you may see at a particular dive site. Try to chat up the dive master long before the actual dive instead of waiting until the dive briefing and then rushing like mad to make the necessary changes to your setup. This approach typically leads to an unpleasant combination of the following: annoyed dive master, irritated buddy, impatient boat mates, and worst of all, flooded housings and ruined cameras and lenses.
Trust me on this one...I've done it—twice—not fun.
With macro lenses, depth of field (the range of the image, from foreground to background, that is in focus) is greatly reduced. So when you want to have as much of the subject as possible in focus, use small apertures (f16, f22, f36, and higher) to maximize depth of field. Conversely, to make only a certain part of your subject stand out against a blurred foreground and background (reduced depth of field), use larger apertures (f2.8, f4, f5.6, and so on).
Let's say you want to photograph a pygmy seahorse (left), which typically grows to be no larger than the size of the nail on your pinky finger (really). At the minimum focus distance from the seahorse, the dimensions of the actual scene that will fill the frame is incredibly small (maybe 2 inches wide or less). Without a tripod or some other device to stabilize the camera, it is basically impossible to use shutter speeds slower than around 1/60 of a second without inadvertently moving the camera and causing the image to appear blurred. For this reason, I almost always use shutter speeds of 1/60, 1/80, 1/125, or even faster, with macro photography.
When you use the above combinations of small apertures and fast shutter speeds, you will need to introduce some artificial light to the situation, either one strobe or two, to properly expose your image. Almost all underwater strobes available today give the shooter the ability to control the strobe output in fractions of full power, for instance: 1/16, 1/4 , 1/2 , and full. The settings that render the proper exposure will depend on several variables: The actual power of the strobe used, the distance between the strobe and the subject, the clarity of the water, and your aperture and shutter speed settings.
Whether you are shooting wide-angle or macro, another potential problem is something called backscatter. In even the best diving conditions, like 150 feet of visibility, minute particles of organic matter suspended in the water column reflect strobe light back to the camera's sensor. What might have been a great shot, ends up looking like you shot during an underwater blizzard. One way to minimize, or even eliminate, this unfortunate phenomenon is to be mindful of your strobe placement and angle. If you move the strobe(s) laterally, as far away from the camera as your strobe arms allow, and then use the edge of the light beam produced to illuminate your subject, a neat thing happens. The light that is coming from the side, rather than head on, reflects off the suspended particles at such an angle that they aren't "seen" by the camera's sensor. Blizzard averted.
If this all sounds complicated, frustrating, and daunting, well...it can be. Like any new endeavor, macro photography requires that you master the learning curve. Experiment with your gear to learn what setting combinations work best for you. Before digital technology changed the entire imaging industry, this process was more complicated because you only had thirty-six exposures to work with on a single roll of film, and you'd have to wait days or weeks to get developed film back to see if you were exposing your shots properly. Now, all you have to do is make an educated guess at the proper settings, take a test exposure, look at your LCD monitor, make whatever adjustments you deem necessary, recompose, and fire away.
After you've been shooting underwater for a while, you'll become familiar enough with your camera and strobe(s) that you will instinctively know what settings to use in different situations. Then you can experiment with adjustments to strobe power, placement, and angles for more creative and innovative images. Good luck.
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Photos by Jeff Yonover (from top): Soft Coral with Porcelain Crabs (Dendronepthia sp. and Lissoporcella sp.) Banda Sea, Indonesia; Squat Lobster on Halgerday Nudibranch (Galathea sp. and Halgerda batangas) East New Britain, PNG; Female Ribbon Eel (Rhinomuraena quaesita) Lembeh Strait, N. Sulawesi, Indonesia; Unclassified Pygmy Seahorse (Hippocampus sp.) Raja Ampat Islands, W. Papua, Indonesia; Pink Anemonefish among Anemone tentacles (Amphiprion perideraion) Kimbe Bay, East New Britain, PNG; and Coralgoby pair protecting eggs laid on aluminum can (Gobiodon sp.) Lembeh Strait, N. Sulawesi, Indonesia.