TTL Flash
Shedding New Light On Close Ups And Macro

A ring flash immediately comes to mind when considering artificial lighting with close-ups and macro. This Canon MR-14EX features a bi-tube configuration, with ratio control between the flash tubes. The ring rotates around the lens axis, letting you emphasize specific subject features. This flash can also serve as a wireless transmitter, should I decide to illuminate the background with a wireless receiving flash.

Any time of year presents us with budding opportunities to shoot close-ups. We can find flowers any time of year, indoors--and possibly even outside. And we're not just limited to plants. Anything within range of a macro lens or any other lens with close-focusing capability is fair game. We just have to know how to master the tools at our disposal, and lighting is a big part of that.

In the past, I would favor available light, since that meant I wouldn't have to deal with flash guide numbers and calculations in my close-up work, especially when working with multiple strobes. Of course, that also inclined me toward shooting at or near maximum aperture and using selective focus (a shallow field of sharpness), often surrounded by a soft blur of color in the out of focus areas. But eventually I wanted more, and when I started using 35mm SLRs (and even medium format) with TTL auto-flash capability, a real solution was at hand with dedicated TTL flash units. Now I could use flash to shoot at or near minimum aperture and get dramatically sharp results.

But my world of close-up TTL flash photography had a few caveats in store. Even now, I was still concerned with movement, but not exactly in terms of camera shake, more in terms of focusing error. For instance, when focusing on a butterfly perched on a blossom, I still had to deal with the slightest breeze that might throw the subject out of focus.

The flexible arms on this Novoflex macro bracket (code name: UNIMARM) make it relatively easy to adjust the position of each flash head, in this case the Novoflex Auto-Duo-Flash, without the need to continuously loosen/tighten joints on an articulated arm.
Then there is also the matter of exposure error resulting from light and dark subject tones or surroundings. I would have to use flash exposure compensation where necessary, adding standard/ambient exposure compensation when using flash as fill. I might also use auto-flash-bracketing (not available with all cameras/flashes).

Even with TTL capability, there was yet one more problem--the flash unit itself, as I'd discovered along a hiking trail on a Caribbean island. I found myself lying on my stomach under a hot tropical sun, with beads of sweat rolling down my face and hands, all in an effort to capture a tiny and very skittish American chameleon. I'd brought along a TTL shoe mount flash and off-camera cable, since I couldn't leave the flash on-camera: The lens (and lens shade) might have blocked some or all of the light and thrown the subject in shadow, even if I'd employed the negative tilt feature on the flash. So, instead, one hand grasped the flash, while the other held the camera--both precariously and uncomfortably. A better alternative to this approach was needed.

Ring flash and twin-light systems require a power module, which houses the batteries. Individual flash tubes or heads may be on/off switchable. Here we see the two tubes of this Canon MR-14EX bi-tube ring flash set for a 1:4 (left to right) output ratio, to give the subject some modeling.

Macro Setup Alternatives
We may be willing to put up with the heft of a shoe mount in hand, in exchange for more power (for smaller f/stops and greater depth of field) and faster recycling (restless subjects don't wait for a flash to power up)--at least for a short while. But what if you had some way to use this strobe in close-up photography that would render it more effective and make it easier to use, especially when you have to employ two flash units together? You definitely don't have enough hands to juggle all this.

One possibility involves the use of a macro bracket. This consists of a base (which attaches to the camera's tripod socket) and two extensions, usually in the form of articulated or flexible arms with individual ball heads, to support up to two flash units (one on either side). Various system components may come as options, beginning with the rudimentary base and arms. Admittedly, this is not a compact alternative. In order to use my existing wireless system, I've used battery-loaded shoe mount strobes with the macro bracket, with the entire assembly mounted on a tripod. With suitable diffusion on each side, this would make a very convenient copy stand setup.

When a ringlight is used on axis with animals or people it has the same effect as an on-camera shoe mount flash, producing redeye, or in the case of my cat, glowing green eyes.
Photos © 2002, Jack Neubart, All Rights Reserved

There are also twin-flash macro systems. These consist of a pair of identical mini strobe heads (sans batteries), connected to a shoe-mounted control module (with batteries). In contrast to battery-laden shoe mounts, this mini-assemblage lightens the load considerably when used with a macro bracket.

Another option exists. While the control module still sits in the hot shoe, the twin mini-heads may come with and attach to a mounting collar (or ring) that fits on the front of the lens, doing away with the need for a bracket entirely. With a collar, the twin-light system is very compact and lightweight--and easy to hand hold. A veritable powerhouse outdoors.

Whichever configuration you choose, twin-light systems offer a good degree of independent movement of each flash head, for optimum positioning, thereby enabling you to tackle a wide variety of subjects most efficiently. Output may be controlled individually on the flash heads and/or in the control module. What's more (provided they are slotted at the front) these mini-heads may even accept drop-in plastic or gel filters (for color effects) or diffusion panels (for a softer light). Compact heads, however, do not generate the same amount of light as a standard-size strobe, and may have limited features.

Catchlights in the eyes (averted to avoid the green-eye effect) clearly reflect the use of a ring flash here.

Twin-head systems obviously have much to offer. But if you don't want to deal with putting these various pieces together, and especially if you want an easier and faster to use and even more compact alternative, consider the ring flash.

Which Ringlight Rings True?
The typical ring flash consists of two key components. As with twin-light systems, there is, first, a control module (also serving as the battery housing) seated in the camera hot shoe. Second is the flash tube housing, which mounts to the front of the lens (via a ring/adapter or directly). Module and flash attach by a cable permanently, or they may be detachable. (Within a product line and where components are sold separately, the same control module may be used with either a ringlight or a twin flash.) The ring flash housing has the freedom to rotate fully around the lens axis.

The macro twin light (in this case, the Canon MT-24EX) provides a combination of flexibility and portability unmatched by any macro lighting system. Focusing lamps (shown on) help with subjects in low light.

The basic concept behind a ringlight is that it consists of a fully circular flash tube behind heavy diffusion, thereby bathing the subject in a soft, even wash of light. This is a form of seemingly shadowless lighting. I say "seemingly shadowless" because, under some circumstances, a faint shadow may be noticeable within the subject, whereas a more discernible shadow may fall on a light-toned backdrop.

Sometimes ringlighting is too flat, perhaps leading to lackluster pictures. Hence a ringlight which actually uses anything but a continuously circular flash tube. The housing may still be circular, but the ring of light actually consists of two semicircular flash tubes. This bi-tube configuration may go one step further, with each flash tube instead being linear, not curved, with as few as two opposing tubes--and perhaps as many as four flash tubes in all, comprising what then amounts to a full circle--in a quasi-rectangular housing.

As a result, each flash tube may act as an independent flash unit, being turned on or off, albeit not independently movable. Select systems even provide for ratioed light output between the two (or more) tubes. Why would you want to switch tubes on or off or control their output? For better modeling. Beyond that, you may be better able to deal with obstructions that might block the light from one side and create objectionable shadows by reducing or eliminating output from that side. With most systems, ringlight and twin flash alike, when one tube/head is shut off, additional power is shunted to the remaining tube(s)/head.

A ring flash might have produced a glaring hot spot in the pool of water that formed toward the lower half of this bromeliad. A macro twin light provided more flexible options and a better guaranty against hot spots. (Lens: 100mm macro; near lifesize.)

For a ring flash to work its magic, the subject should be the same size as or smaller than the diameter of the ring, but that's not a mandate, since the flash can also be used more conventionally off the lens. Owing to the ring flash head's close proximity to the subject, it should be possible to stop down to very small apertures to enhance depth of field. And because it mounts directly to the front of the lens, and has a generally small diameter, a ringlight lets you squeeze in between tree branches and other tight spaces to provide good illumination of subjects that are otherwise hard to cover with another light source.

The one drawback to a ring flash may also be one of its strongest assets. Ringlights are not very powerful, so that even in bright light, backgrounds are subdued when the right combination of small f/stop and 1/125 sec or faster sync speed is used (other combinations may also work). In other words, the opportunity to create dramatic backdrops with close-up and macro subjects presents itself at almost every turn. This may also apply to macro twin-light systems, provided both heads are aimed at the subject, not beyond.

Some twin-light systems and many ringlights come with an additional feature built-in, something not found on the typical hot shoe flash. This element is a focusing lamp (or set of lamps) that makes it easier to see a subject in subdued lighting or through slow optics.

I tried this shot of tiny seashells in the sand with three different sets of flash units attached to a Novoflex macro bracket with flexible arms. First was the Novoflex Auto-Duo-Flash; second was wireless, with a combination of a Sigma EF-500 Super and Canon 420EX, followed by a pair of 420EX units in the final variation. While mini-heads are a bit easier to work with, the wireless solution let me take advantage of the modeling flash function of the Sigma and Canon units. (Lens: 100mm macro.)

So these days, shooting close-ups with flash has become second nature, thanks to TTL control. Bring on those skittish chameleons. I'm fully prepared to photograph them this time--in a flash.

Macro Flash Tips
What follows are general guidelines. Every situation is a judgment call. You may have to adapt equipment to the needs at hand by modifying techniques or approaching the subject in a more innovative fashion. Or you may simply want to take a more creative tack.

· Three-dimensional subjects with an obstructed view. Use a ring flash, since it penetrates barriers and opens up areas that might otherwise be thrown into shadow (such as a bug among the foliage or the interior of a flower). Ring flash configurations that fully encircle the subject may be preferable if you wish to blanket the subject area in light. Where part of a curving leaf obstructs the light, use a bi-tube/multi-tube ringlight and shut off or tone down the light on the offending side. Working with a more contrasty light also adds snap and enlivens colors with any subject photographed by a ring flash.

· Three-dimensional subjects with an unobstructed view. If the subject is very small, use a bi-tube or multi-tube ring flash or a twin-flash system (ratio light output for a modeled effect, where possible). For subjects that are larger and/or farther away, (with the appropriate lens and, if necessary, the proper lens attachments for close-up/macro), use a dual-flash system on a macro bracket. Try to avoid casting double shadows.

· Artwork and flat objects. Because of the potential for glaring hot spots, non-movable flash systems (namely, ringlight and on-camera flash) should be avoided. Use an on-lens twin flash (for postage stamps, coins, other things this size) or a bracket-mounted dual-flash system (for larger subjects) in a copy stand-like setup (each head at a 45Þ angle relative to subject), equidistant on both sides. The lighting should be diffused to ensure that it's as even as possible.

· Glossy and mirror-surfaced subjects. Some sheen adds sparkle to a shot and conveys a sense of the subject's nature; other times it may be objectionable--this is as much an artistic as a technical call. As with artwork, a two-flash system is needed. If you suspect serious surface reflections, use a light tent. An alternate approach simply calls for diffusing each flash to prevent those glaring hot spots. I may use one or two (or more) layers of a white handkerchief or those thin, semitranslucent white foam sheets that are used in packaging, sometimes resorting to commercial diffusers--or a combination of these. Bounce flash also works, but the excessive loss of light may result in larger f/stops and less depth of field. Cross-polarization (one polarizer on the lens, another on each flash head) may help to eliminate reflections where absolutely necessary, with a resulting substantial light loss. You can buy sheets of polarizing film (for use on flash, not the lens) at photo-supply outlets. (Caution: flash tubes get hot, and anything covering them should be inspected regularly to prevent it from melting or igniting. Provide breathing room, and avoid placing plastics or any flammable material directly against the flash face.)

· Zoo subjects behind glass, terrariums, and display cases. Either a twin-tube on-lens macro flash (for very small subjects at/near the front) or a dual-flash bracketed system (for larger and more distant subjects), with flash tubes angled toward subject, to prevent/limit reflections off the back of a case. Keep the flash heads against the glass, if possible, to prevent flare, and use a lens shade. Restrict light reach to subject by using small f/stops. Lights should be diffused when aimed at shiny surfaces. For small displays, it may help to use a 50mm macro lens or a close-focusing 28mm or 35mm optic; a 100mm macro (or thereabouts) for larger displays--all depending on subject distance and size. With small terrariums, especially those with a glass/acrylic lid, you may want to try positioning a "sun" light above, with a second light from front or side as fill. Watch for obstructions, such as plants, rocks, and ornaments, which might block the light and cast shadows. The lens should be held flush against the glass, where possible, to prevent distortion, as well as to avoid catching reflections in the picture.

· Aquariums. Either a twin-tube on-lens macro flash or preferably something with more flexibility and reach, namely a dual-flash bracketed system (with flash tubes equidistant for moving subjects). To prevent or largely alleviate backscatter (myriad hot reflections) that results when light directly hits floating particles in the water, angle flash heads toward subject, not squarely, and position them against or as close to the glass as possible, and use a lens shade against flare. Try to avoid low-lighting angles, as unnatural, in favor of a more naturalistic light from overhead somewhat. Increase depth of field and restrict light reach to subject by using small f/stops. Lights should be diffused to prevent glaring hot spots off shiny scales. Anything from a 90mm or 100mm macro to a 28mm lens with or without close-up attachment will work nicely, depending on size of aquarium. Hold the lens flush against the glass to improve image quality.

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