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Close-Up Nature Photography By Robert Winkler
The next step—getting them on film—entails specialized tools and precise techniques. To do the job right, begin with a single-lens reflex camera. An SLR lets you change lenses and use lens attachments, and its through-the-lens viewing shows exactly how a subject will appear on film, without the parallax problem that occurs with other camera types. Even with an SLR, you need special equipment because the standard 50-mm lens rarely focuses closer than 18 inches. This keeps you too far away for a frame-filling picture of, say, an average-size flower. If you've never done close-up photography, it pays to approach your small subjects step by step. This way, you may find that the simplest modifications to your camera outfit take you as near to your subjects as you want to go. If later you decide to tackle greater detail or smaller subjects, you'll benefit from the additive nature of close-up photography's tools. You can often use old and new equipment together for higher magnifications. So before you spring for a macro lens, try cheaper alternatives. The simplest way to photograph flowers and other common close-up subjects—leaves, fruits, and very large insects such as butterflies—is with attachments known as supplementary close-up lenses. Usually sold by lens manufacturers in sets of three, with diopter values of +1, +2, and +3, they function like filters, screwing onto the front end of your lens. You can use them singly or in combination to obtain different magnifications. When using more than one, always place the higher diopter value closer to the camera lens. Note that optical quality can suffer markedly if you use more than two supplementary lenses at a time. Smaller subjects demand the higher magnifications of extension tubes. Placed between the camera and lens, extension tubes let you focus with the lens closer to the subject. They range in length from about 7 mm to 50 mm. The longer the tube, the closer you can get. For a jittery subject such as a butterfly, using a tube with a 100-mm telephoto lens gives adequate magnification from a comfortable distance. When buying extension tubes, look to your lens manufacturer, and make sure you buy auto extension tubes that couple to your lens's automatic diaphragm, permitting normal camera operation. Virtually all SLR cameras have through-the-lens light metering that will automatically compensate for the required increase in exposure.
Extreme close-ups are best handled with a macro lens. While conventional lenses perform best when focused at infinity, macros deliver optimum image quality at close range. A 50-mm or 55-mm macro typically delivers half-life-size reproduction—powerful enough for parts of large flowers, single small blossoms, hefty insects, and textural details of wood and stone. Longer macros such as 105 mm, 135 mm, and 200 mm are best for amphibians, small reptiles and mammals, and other subjects that may not tolerate the close camera position necessary with a 50-mm or 55-mm lens. A macro zoom gives you close-up capability in a lens with a variable focal length, though you must usually pay for this flexibility with a slight sacrifice in image quality. To reach the life-size 1:1 reproduction ratio that defines a macro, in which the film image equals the size of the subject, you'll probably need, once again, an extension tube or, preferably, a bellows. Although more cumbersome than extension tubes, a bellows allows greater lens extension and thereby higher magnifications. It also is infinitely adjustable across its length. Macro lenses used at their highest magnifications (life-size and greater) can reveal hidden details: a flower's individual pollen grains, an insect's segmented eyes, a leaf's most minute venation. When you photograph small things large-scale, a minute adjustment makes a vast difference and a slight error becomes greatly magnified. Depth of field decreases as you get closer to a subject—although measured in feet or even yards at normal distances, it shrinks to millimeters in close-up work. With the modest magnifications of supplementary close-up lenses and short extension tubes, you can often handhold the camera and still get decent depth of field. However, for acceptable focus in extreme close-ups, you may need to use your lens's smallest aperture, and to compensate for the longer exposure time this aperture necessitates, you'll need a tripod. One that shortens to nearly ground level has obvious advantages; a geared center column lets you raise or lower the camera with precision. A focusing stage between the tripod and the camera—consisting of two geared rails for moving the camera back and forth or side to side—lets you largely dispense with the lens focusing ring, a mechanism too coarse for high magnifications. If your camera has a mirror-lockup feature, you can use it to reduce vibrations at the moment of exposure. Because a slight breeze can throw off the focus, wait for a lull if you're contending with the wind. Otherwise, use some sort of windscreen, move a willing subject inside, or take advantage of the motion-stopping ability and brightness of a flash. Although you don't need a high-powered flash with small close-up subjects, you do need through-the-lens flash metering to compensate for the presence of an extension tube or a bellows. You also need to aim the light precisely. A macro flash unit that encircles the lens (called a ring flash) puts even illumination where it belongs. The restricted subject matter of close-up photography simplifies
composition. A flower blossom can stand alone; a section of tree bark can
fill the frame from edge to edge. Depth of field is so narrow that most
backgrounds will be a pleasant blur. Do, however, watch backgrounds for
distracting blobs of light, best eliminated by a change in camera position.
Don't worry if you can't get the entire subject in focus. Decide which
pictorial elements are most important, and focus on them.
Text and photo ("Monarch on Thistle") Copyright © 2006
Robert Winkler
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have a friend
who, when we walk together in the woods, will spot the tiny salamander upon
which I, unaware, am about to step. She will be the first to notice the
bright green clump of furry moss that clings to an edge of bare rock on the
cluttered forest floor, the perfectly formed and strangely beautiful fungus
growing on the dark side of a tree trunk. Her eyes will pierce the woodland
shade to detect a bird that, alone, I would miss. She'll find fascinating
geometry in the patterns of leaves; animate life, human form, and even humor
in dead wood. From her, I have learned to see and to wonder at the things
that dwell in worlds through which we move as giants. On outings with people
who share this acute sensitivity to the small and subtle, any photographer
can learn to appreciate the miniature wonders of nature.
