Working with one light and fill

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How many lights do you need, anyway? You might be surprised to learn that you can do an exemplary job with very few lights—often only one—provided you understand your equipment and why it works the way it does. Understand that I’m not talking about an oncamera flash; those small, specular sources that throw hard shadows and bright highlights. Ideally, you’ll need at least one studio strobe and at least one quality modifier like an umbrella or softbox, and the larger the better.

But first, a little background.

Beauty and glamour photography frequently relies on soft, open shadows to show the subject in a beautiful and youthful manner, and this is usually accomplished by using a large, diffused light source. It is important to note, though, that placing a large source far from the subject will make it small relative to the subject and will make it act like a small source. For a thorough and exhaustive investigation of this phenomenon, please see Christopher Grey’s Studio Lighting Techniques for Photography.

I’ve heard many so-called formulas for determining the optimum subject-to-light distance for softboxes, some of which might require a degree fromMIT to understand. In my opinion, the optimum distance equals the sum of the height and width of the box. Using my homespun formula, a 2×3-foot box would be placed 5 feet from the subject, while a 4×6-foot would require 10 feet to throw light without specular highlights but with perfectly defined yet open and soft shadows.

The effect of the light-to-subject distance can also be seen when using an umbrella, another modifier most photographers have. The most frequently purchased umbrella has a 36-inch diameter, but if you’re in the market for them or want to add to your existing stock, I’d recommend that you purchase the largest one you can find and afford. The additional size means you can move the umbrella farther away while maintaining a softer look. You can also buy what are known as “shootthrough” umbrellas, made with translucent material. Unlike traditional umbrellas, shoot-throughs are aimed at the subject, acting more like a softbox than an umbrella.

We’ve all heard of the Inverse Square Law (even if we’ve never understood it), which states that light that travels twice as far from point B to point C as it does from point A to point B will be only 1/4 its strength when it gets to point C than it is at Point B. In simple, practical terms, this means that a light that’s placed

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close to a subject will lose its strength rapidly, maintaining a constant f-stop value over a very short distance. Conversely, a light that’s placed farther away will maintain a constant f-stop value over a greater distance. This phenomenon is known as “depth of light,” and it is something to be exploited when envisioning an image.

The bottom line is that you can be extremely creative with minimal equipment when you know how you can change the characteristics of the light that’s produced.

Let’s take a look at some terrific ways to work with a single light.

Perhaps the most important lesson to be learned when working with a single light is that it can be made to look like more than one source. This can be accomplished in a number of ways, with one of the simplest being the use of various bookends and reflectors.

By itself, image 3.1, made against a white seamless background, is dramatic but lacks detail that would make it more interesting. As you can see in diagram 3A, my medium softbox was set to camera right, racked high enough to get a graceful nose shadow and placed at a distance of 7 feet from the model. My model was placed about 7 feet from the background, to be certain that enough light would fall upon it to keep it bright enough to show the shape of her shadow side but dark enough so the image would have a sense of depth.

Simply adding a white bookend to the shadow side softened and opened up the dark tones, giving the impression of a second light. I prefer reflectors over additional lights because extra sources tend to show secondary shadows on the opposite side of the nose and double catchlights in the eyes. The effect of reflectors is much softer. See image 3.2.

You can also change the shape of the light falling on the background by inserting a bookend between the main light and the background. For this image, I quickly cut a shape into a black piece of foamcore, attached it to an accessory arm on a light stand a few feet from the main light, just behind the model, then moved it into place to keep about half of the light off the background in those places where I wanted it reduced. It was close enough to the main light to guarantee the shadow on the background would be soft and undefined. Moving the form closer to the background would sharpen the shadow line. Note how the gobo shadow gives the impression of a second light on the background. See images 3.3 and 3.4.

Let’s change things a bit and move the light to 90 degrees to the camera, so it’s essentially behind the subject should she turn her head to profile. This is a variation on the broad light position, where the light comes from behind and across the side of the face that’s presented to camera. Notice how beautiful her profile looks when in shadow, as well as the sense of mystery achieved from lack of detail. See image 3.5.

This sense of mystery may be too much for many images, and you may wish to use fill to open up the deep shadows. A bookend, in this instance, may add too much light or not enough contrast (depending on what you’re trying to achieve), although it is soft and beautiful light. You will be able to vary the effect by moving the bookend closer to or farther from the model. Image 3.6 was made with a bookend far enough from the model to bounce back –1 stop of light.

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I use the next lighting scenario quite often, just because it’s so easy and versatile. By changing the three elements (the main light modifier, type of fill, or distance of the main light from the subject), I’m able to create a wide variety of looks. This image, made on a different shoot, utilized a painted canvas background, a smaller softbox (2×3 feet) set very close to the model (but not aimed directly at her face), and a white bookend set about 5 feet from her, far enough away to keep the shadow dark but close enough to reflect a little detail, –1 stop, into the model’s camera-left side. I also inserted a black bookend at camera right to break up the light falling on the background. See image 3.7 and diagram 3B.

Most images are made with the main light positioned above the model’s head, to produce a graceful nose shadow. As long as you’re mindful of where the shadows fall, you can place the main light at other elevations, too. For this example (image 3.8), I used a 3×4-foot softbox but set it low, with its lowest edge just a few inches from the floor and angled up toward the model. The light was placed far enough from the model so it would also light the background behind her, about 4 feet away. I also set my model closer to the background than usual, about 5 feet, to maintain a more even light. I did not use a bookend or other fill, preferring to let the shadows go dark.

Having such a low main light proved to be more versatile than one might think. By reversing the pose, asking my model to angle up and away from the light, the non-filled shadows created a very dramatic image (3.9).

As simple as these principles appear, they can be easily used to create outstanding drama.

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The bookend is a large, broad platform that will bounce soft light. For a tighter and more contrasty fill, try a small reflector—silver, white or otherwise—and aim the bounce at the model’s face. I use a number of Lastolite reflectors (www.lastolite.com) in my studio, but the brand is not as important as the size; the smaller the size, the less area will be accented, and this is another trait you can exploit to match your personal style. As I did with the bookend, you should make exposure strength tests with your gear so you’ll have a better idea of what to expect.

BUTTERFLY LIGHTWITH THE SUBJECT CLOSE TO THE BACKGROUND

Butterfly light, the term given to light produced from a source placed high and directly over the lens axis, is beautiful for women. As a single-source light, it can produce wonderful images either when the model is placed close to the background, so as to include her shadow in the composition, or far enough away to isolate her from the background so her shadow has no effect. With the latter, I think you’ll want to keep the light on the background bright enough so the background looks deliberately lit. Also, when using this scenario on a dark background, be careful to keep enough light on it so as to show the model’s complete shape, even in the deepest shadows.

For this shoot, I placed my model into a corner of the studio that I’d painted semigloss gray. Even though semigloss paint may show some reflection from lights, especially with darker colors, the overall effect has more visual impact than flat latex wall paint, an important quality for much beauty and glamour work. Also, painted sheetrock has a flatter texture than seamless paper, which contributes to the look of the final image.

For this shot, the model was very close to the wall, as you can see from her shadow. The large softbox was my only light. It was positioned behind and above me but close enough to the model so it produced only broad, soft shadows. Because my softbox was set horizontally, and parallel to the wall, the exposure was consistent across the entire 5-foot painted expanse. My model was free to move about within that space as she wished, provided she stayed close to the wall. If she had moved more than a few inches toward me, there was a danger she would begin to overexpose. See image 3.10.

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With the light set behind me and the camera handheld, I was able to move around within the frame. This meant I was not tied down to the butterfly position and could vary the direction of the source by not having to move it. This degree of versatility and adaptability can be crucial to the success of fashion and beauty shots. In this case, I was able to use a number of shadow and wardrobe variations to produce a great series of images. See image 3.11.

Large or medium softboxes can readily be used anytime you wish to light a large portion of the model with minimal shadow contouring, regardless of the model’s position. Should you pose the model reclining on her back, you must correlate the position of the light to the model’s facial pose and her nose shadow. In many scenarios, photographers light the model from the side, with the light centered. This is a mistake. When the light is sourced from anywhere near the model’s face (as it would be if aimed at her side), the shadow cannot travel down the nose as it should. It can only travel sideways or, worse, if it’s placed below eye level, up toward the forehead.

You can get a much more even spread of light by “feathering” it over the model, which is to say that after you set it to get the right shadow, you’ll actually aim the strobe head toward her feet. Even though you’re working with a softbox, the light will not be even if it is not aimed properly. In fact, given the spread of light from a softbox, if you simply aim the head at your model’s face, you’re actually wasting half the output. Use your meter to gauge the spread of light.

SINGLE UMBRELLA

Getting terrific results from a single source and umbrella is as easy as working with a softbox, although the results will look different. Umbrellas are designed to spray the light from a smaller source in all directions, expanding the illumination. This makes them difficult to deal with when the light must be controlled. In my opinion, therefore, umbrellas are not the best modifiers to use for background or hair lights.

The only controls we have when using a single umbrella are the angle of incidence to the model and the light-to-subject distance, which will determine the strength of the shadow and the consistency of exposure. For this image, I placed a basic, 36-inch umbrella on a boom and raised it to about 3 feet above and 3 feet in front of her. This woman is 6 feet tall, so I knew, with the Inverse Square Law on my side, that the light that made it to the floor would be 1/4 the strength of the light that lit her face, a 2-stop difference. Since my intention was to not show her feet, I was confident I would have quality light that would gently fall off as it traveled down her body, with the emphasis on her beautiful face.

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A word of caution here: keep an eye on the position of your model’s head. Should she tilt her head down too far, the shadows in her eye sockets may be too dark. In image 3.12, the model stopped just shy of that point, but she looks good.

BROAD SOURCE FROM ACCESSORY FLASH

Please note that while this is an effective way to create a large source from a small one, it will require an external flash meter, as using auto or TTL settings on the flash will not give you the correct flash output to get accurate exposure (the flash unit will actually read the bounce coming back from the diffusion panel). You will only be able to gauge exposure correctly using a combination of manual flash mode and a handheld flash meter. Though it can be done, it presents a number of problems, not the least of which is waiting for the strobes to recycle. See the accessory flash diffusion discussion for more information.

THE BOOKEND BOUNCE

I’ve written of this before, but it’s worth repeating because it’s such a cool and inexpensive trick.

Deadlines can be wonderful things. Some time ago, I was faced with a monthly column deadline and was dealing with a mild case of writer’s block. As I paced the studio floor and glanced at my stack of bookends leaning against the wall, it occurred to me that I’d been curious to know if a bookend could be turned into a main light and how I might use that main light effectively. I had my column idea. I just had to figure out how to make it work.

I began by cutting a hole, about three times the diameter of my lens and at my comfortable shooting height, into the spine of the bookend. I knew that when a model was placed in front of it, the bookend’s white surface would reflect light evenly over her. By itself, this could be a good thing, but I also knew that the completely white reflection would carry across her eyes, glazing her pupils and giving her that “model of the living dead” look we should always try to avoid.

To break up the reflection, I sprayed a radiating pattern of flat black paint, varying the length of the strokes between 11/2 to 2 feet from the center of the hole. This would reflect black onto her irises, giving her eyes color and depth. See image 3.13.

Once the paint was dry, I set the bookend about 12 feet from the background, with the V opened toward the model. I put her in position, no more than 3 feet from the V and facing the cutout.

Next, I set up a strobe with a parabolic reflector on a boom arm and suspended it about 6 feet behind her, aimed at the back of her head but also toward the top of the bookend. If your model has deep-set eyes, the reflection can create a shadow above the lower orbit. It’s easy to fix in Photoshop, but the idea is to keep postproduction to a minimum. An angle such as this means the light will mostly bounce down to the subject.

The distance from the light to the model meant that she would be evenly lit across the rim of her hair, shoulders, and back, and also that the entire bookend would be awash with light, which would reflect back to her to light her softly.

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The single strobe was shining directly onto the camera lens, which would produce more than enough flare to ruin my shots, so I hung a piece of black card, about a foot square, directly over her head on another boom arm, to throw a gobo shadow that covered the shooting hole. Now I was free to place the camera anywhere I wished within the cutout area without worrying about lens flare.

With the model in position, I placed the light meter under her chin and aimed it at the hole where my camera would be. The light reflecting from the bookend then became the main light for my shot. I knew that the light on the back of her head would overexpose whatever it hit, but I saw that as a necessary element of the shot, something that would add visual interest.

When you try this, you’ll know from the first shot that you’re seeing something unique. The wraparound bounce from the bookend acts like a huge ring light, spreading illumination evenly over the subject and lighting the background as well (anything darker than a medium gray will photograph black or almost black at the distance I’ve suggested), while the hair light, with its extreme overexposure, adds drama and contrast. Additionally the eyes carry wonderful color and large, soft, catchlights. See image 3.14.

It’s not necessary for the model to always face the camera. She’ll be evenly lit no matter which direction she faces. With a scenario like this, a dramatic head tilt will equal a dramatic image. See image 3.15.

While I really liked the two-light look I’d achieved with only one light, I felt there was still room to improve the look, maybe to even give the impression of a third light.

You can stop in to just about any large hardware store and buy a box of lightweight, one-foot-square mirrored tiles that are meant to be glued to various surfaces. I taped a 4-inch nail plate to a single mirror panel and mounted it into a clamp on the second boom arm, in place of the black gobo. The mirror would serve as a gobo to keep light off the camera and would also reflect light behind the subject, acting as a third, background light. See diagram 3C.

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I’ve set this up many times since first figuring it out and the exposure results are quite consistent, given the distances I used. The light hitting the back of the head will be about 2 stops over the metered main light, and the light from the mirror will be about 1 stop over the main light. It doesn’t matter, though. Soft but dramatic light is the goal; the only important light is that reflected from the panels. See image 3.16.

Be sure to do a custom white balance off the bookend. Foamcore yellows with age, which will affect the subject’s overall color. Of course, if it gets too old and yellow, the other light in the image will look cooler, as blue is being added in the camera to compensate for the yellow the camera sees when white balancing.

MIRRORS AS MAIN LIGHTS

You can easily change the look of this one-light scenario by removing the bookend bounce panel and using the mirror to shine light onto the subject. When the mirrored light becomes the main light, the subject will still pop out of the background, but any portion of the background not hit by the new main light will appear very dark, as minimal light will be falling upon it. You will have to play with the angles a bit to get an attractive shadow on the model’s face, and it might be a good idea to hang a larger gobo between the backlight and you, to give yourself a larger shadow to work under. See image 3.17.

Larger mirrors may also be used as fill or hair lights, although reflected light will have the same properties of the source. So, if the source is a hard light, the reflected light will be just as hard and shadowy, unless the mirror is somehow modified, perhaps with water-soluble dulling spray or diffusion material such as that made by Rosco.

Setting up a good lighting scenario takes time, thought, and pre-visualization. If I’ve been hired to produce just one look for a final image, perhaps a shot of a model in a specific composition (such as I might have to do for an advertising job), I’ll spend additional time during the shoot watching the model’s position and tweaking the lights and their ratios to the main light until the client and I are completely satisfied. However, if I’m shooting for stock, the model’s portfolio, or just to play, I’ll try to engineer potential variations into my scenario, to get as much variety out of it as possible. It’s much easier to make small changes to get a different look than it is to relight an entire set, even when using only one light.

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