Outdoor Lighting

Homemade gadgets to help your outdoor lighting by Kery T. Givens Md

Everyone's a specialist nowadays. That's the old gripe. As A physician, I hear it every day. But medicine doesn't have a monopoly on specialisation. In fact, when it comes to esoteric careers, the world of photography boast many job descriptions that are, well highly focused. And sub-specialisation is common place. I know one guy who gets a little offended if you describe him as a food photographer; as he's quick to remind you, he's a dessert photographer. If current trends continue, he'll probably end up even more specialised, photographing only frozen chocolate desserts. Despite the narrow careers in this business, photographers remain united by a common goal: to control light. We all manipulate light, i.e., herding photons down lens hoods, through filters and wads of lenses.

Controlling light at its source, even before it reaches the subject, obviously provides the photographer with terrific artistic control. Especially in macrophotography - one of my own favourite niches - the photographer can maximise this control, since the subjects (and hence the areas requiring illumination) are small. What follows are some simple, inexpensive lighting techniques I've found effective in outdoor close-up work.

Made in the shade

Nature photographers like myself are often pale-looking folks, since we have a tendency to concentrate our shooting in early morning and late afternoon, fleeing the sun like vampires. Why? One reason is that the direct sunlight of midday makes for very contrasty pictures, full of harsh shadows and / or washed-out highlights. True, the interplay of shadow and light can sometimes strengthen an image, but just as often obscures subject details. By shooting at dawn and early evening, shadow problem are minimised, thanks to the diffused quality of the light. Similar diffusion results when a thin layer of clouds roll over a sunny sky, yielding the oft-mentioned but too-seldom-seen "bright overcast."

If you limit your photography to dawn, dusk, and overcast days, you'll miss incredible number of picture opportunities. My solution: Why wait for diffuse lighting when you can make your own? Small areas of harsh , direct light can be readily converted into pleasantly diffused light in a variety of ways. One straightforward approach is simply to block the light, casting the subject completely into shadow. For several reasons, total shadow is not the ideal solution. True, it is certainly reduces the contrast problem, but at a price. First, it may reduce the contrast too much. When available light is highly diffused ( as it is in shade), the small highlights and shadows that normally enhance surface texture may disappear, causing a subject to lose its three-dimensional appearance- hence the expression "flat lighting." Also, shaded subjects obviously require a longer exposure than fully sunlit ones- two to three stops longer when going from full sun to complete shade. Throw in a little lens extension ( to provide close up magnification) and slow film ( necessary in today's editorial market), and extremely long shutter speeds may result. My slide collection is full of 8 - 20 second exposures.

A sturdy tripod and cable release make long exposures manageable, but accurately computing very long shutter speeds can be a little dicey. While most SLRs will meter down to 1 or 2 seconds, the metering scale on many models stops there. One solution is to double or quadruple the ISO setting on the camera, meter the scene again, then divide the resulting shutter speed by two or four, resulting shutter speed by two or four, respectively. Alternatively, a good hand held meter will usually be able to register exposure down to 20 seconds or so without difficulty. Especially with Kodachrome emulsions, long exposures sometimes may result in strangely tinted images. Some of this is simply due to the colour temperature of the light reaching the shaded subject. Consider a white flower growing under a canopy of deciduous trees: The layer of green high overhead not only blocks sunlight, it filters it, shifting its spectrum ( and hence the apparent colour of the flower ) toward blue-green. Also, the phenomenon of reciprocity failure (RF) may influence the colour , particularly with very long exposures. RF occurs because different dyes in the emulsion do not react to light at the same rate. Although RF is minimal with short exposures- less than one second - the longer exposure, the more pronounced the effect. RF can be combatted by intentionally lengthening the exposure ( I usually expose at 1 Â1/2 times the calculated shutter speed) and adding filters.

Modified Shade

In short, casting your subjects into total shade is not the best solution for strong, direct light. Many of the problems of full shade can be ameliorated, however, by selectively restoring a little light to shaded subject. How? Using a fill-in flash is one option. After a few years of fighting with NiCds that never lasted as long as they were supposed to, too-heavy battery packs, a series of defective flash cords, and time-wasting calculations of flash power and f-stop ratios, I abandoned high technology for something a little more primitive: a piece of corrugated cardboard covered with aluminium foil. I invite, fill-in flash users to guffaw heartily; I've published plenty of photos illuminated this way.

The technique is simple. After blocking all the sunlight falling on a subject-say, by standing between the sun and the subject - hold the reflector off to the side, angling a beam of light back onto the subject. The beam from this sort of reflector is agreeably diffuse, especially if the foil has been crinkled before applying it to the backing. The intensity of the light can be varied simply by changing the angle of the reflector and its distance from the subject. Don't count on getting a big change in exposure with this sort of fill-in. A gain of one f-stop or less is the rule, unless you're reflecting strong, direct sunlight. Nonetheless, improved subject texture and detail are usually visible in the final picture. And by carefully aiming the fill-in light, it's possible to isolate the subject from the dimly lit background, further enhancing its three dimensional quality. A final bonus: When photographing wildflowers , the reflectors act as a windbreak.

If aluminium is just to reflective for your tastes, a plain white care will provide more subtle bounced lighting. I prefer Bristol board, a heavy grade of drawing board available a most art supply houses. Because it is much less reflective than aluminium foil, a white card works best with very strong available light. Even with this lighting, you'll probably have to hold the card very close to the subject to see and effect. By positioning an aluminium reflector one side of a subject and a white card ( or second foil reflector) on the other , one can simulate multiple fill-in flashes. I won't lie-setting up two different reflectors and simultaneously operating the camera takes some practice. But multiple flashes are even more awkward, usually demanding special brackets, extension cords, and / or tolerant assistant. I've folded my reflectors in half, like giant greeting cards, so they can stand up on their own. This frees at least one hand, allowing me to operate the camera with a cable release while positioning a second reflector with my other hand.

An even simpler way to stimulate bright overcast is by passing sunlight through a translucent material such as cloth or plastic. Still looking for a gift for the Photographer Who Has Everything? You may have seen ads for a little diffusion tent, specially designed for close-ups subjects. The tent, which is erected over the subject, is made of a diaphanous fabric that converts blaring sunlight into soft, evening lighting. I'm sure it's very effective, but personally I have little desire to erect a tent for every close-up picture.

My answer is simpler. I carry a sheet of clear plexiglass, heavily scratched on both sides with steel wool. These scuffmarks greatly diffuse light passing through the plastic. With strongly lit subjects, simply hold the plastic between the sun and the subject-you get instant diffusion, and no risk of putting out an eye with a tent pole. Some photographers I know carry a small white umbrella for diffusion. I've tried it, and it works fine. Hanging onto the diffuser can sometimes be challenging, however, on windy days. On the other hand, this approach has the added advantage of waterproofing the photographer and his equipment in the event of unexpected showers.

It's all done with....

Consider an object silhouetted by setting sun. How can you bring out details on the subject without grossly overexposing the background-and without using fill-in flash? You could try bouncing light back onto the subject with aluminium foil reflector, but you probably won't get enough reflection- the subject would still end up a few f-stops short of the background. A better solution is bounce the light with a mirror. Granted, the thought of a fragile sheet of plate glass colliding with lenses in you gadget bag does not seem too desirable. Fortunately , high technology has made that risk unnecessary. Most glass suppliers carry "plexy mirrors" that is, clear plastic backed by silvery, mirror-like Mylar. Not only are these mirrors shatterproof, they're also cheap and much lighter than their glass counterparts.

In very poorly lit settings, a mirror is a much more efficient reflector than aluminium foil. You don't need a big one. The one I carry is about 8 x 12 inches, ample for every situation that has required its services. Although it cannot be neatly folded up for storage, its versatility makes up for this small impracticality. I've glued a sheet of white paper to the back of my mirror, so it doubles as a white-card reflector. If you're the type who simply must have an 18% grey card at all times, you could glue that on, instead. I've also used mirrors for background control. In particular, a mirror can help create a suitable background where one doesn't exist. With flowers or other small subjects, a uniform, out-of-focus background helps simplify composition, calling attention to the colors and geometry of the subject itself. Unfortunately, such backgrounds are not always around when you need them. And it may not be ethical (or even possible!) to uprooted the subject, in order to reposition it in front of a desirable background.

A mirror lets me bring in the background I want without moving anything. The process is straightforward. First, focus the camera on the subject. Next, position the mirror facing the camera, on the far side of the subject. By pivoting the mirror (like a door), all the while keeping it directly behind the subject, a photographer can often "drag" more aesthetic scenery into the background of the image. Ideally, the mirror should reflect scenery that is as far away as possible; because of the narrow depth of field common to close-up lenses, this will ensure that the background will appear out of focus in the final picture.

Once I was trying to photograph the tip of a small bamboo shoot emerging in my lawn. The background was a jumbled, distracting mess of tall grass, too close and too contrasty to blur by using a wide aperture. The mirror didn't help either not matter how I turned it, all it showed me was more confusing, trangled grass. So I selected a very slow shutter speed, positioned the mirror in the background (reflecting some grass off to the side) and wiggled it slightly during the shot. In the final picture, my subject stands out against a soft unfocused background of green. I've used this trick successfully many times. The hardest part is keeping the edge of the mirror from showing up in the picture, since it's tricky to shake the mirror while looking through the viewfinder.

Rimlighting

Backlighting or rim-lighting of small subjects can also be accomplished with mirrors. This technique can be quite effective when photographing leaves, flowers, or mushrooms. Many fungi, I have found have marvellous translucent quality when lit from behind. Fortunately, they are among the most stoic nature subjects, posing unflinchingly; while the photographer explores different lighting angles. Note: With back-lighting, unwanted glare is always a risk; be careful not to bounce a shaft of light directly onto the front lens element or filter. A long lens hood averts this problem. In a pinch, a sheet of paper rolled into a tube and slipped over your lens will suffice. Correct exposure is admittedly, a little trickier with back-lit subjects. With back-lighting , many camera meters will be fooled by the intensity of the light, tending to underexpose the entire image. Even with today's sophisticated reflected-light meters, bracketing is still the best bet.

There was a day when I toted bellows, flash brackets, and other heavy photographic esoterica on every outing. And from time to time, I still use that stuff. But seeing what a few pieces of cardboard and some aluminium foil can do has taught me that there's still a place for low tech. After all, in the business of making great pictures, the most important element is not the sophistication of the gear- it's the ability of the photographer to control light.