Lighten Up!: What the Pros Know

Here’s a quick three-part quiz for you to take:

Which offers better image quality?

1. poorly lit, first-generation VHS footage
2. poorly lit, second-generation VHS footage
3. well-lit, third-generation VHS footage

Which looks best?

1. poorly lit video from a $10,000 camcorder
2. poorly lit video from a $2,000 camcorder
3. well-lit video from a $500 camcorder

Finally, which offers the best-looking images?

1. poorly-lit DV video
2. poorly-lit Hi8 video
3. well-lit VHS video

If you answered "C" to all three questions, you’re right on the money. More than number of generations, the price of your camcorder or the format used, good lighting is the key to good image quality. Don’t believe it? Set up an actual head-to-head comparison based on any of the three questions above. The well-lit video will win out over the poorly lit variety every time.

Professionals understand the importance of good lighting, and they take lighting their shots very seriously. In this article, we’ll explore what the professionals know about lighting, what they do with that knowledge, and how you can learn from them to light your own videos like a pro.

To supplement this article, do some homework from your living-room couch. Your assignment is simple: watch any TV show or motion picture with an eye towards the lighting. Watch for shiny surfaces (especially eyes and eyeglasses, car windows, metal objects, etc.) that reflect the actual light sources used in the shot. These objects reveal much about the lighting used: what type of light, its position, even the size of the source. In time, you’ll recognize many of the techniques we’ll discuss in the next few pages.

Also, spend some time experimenting with lighting. Set up a few lights, a camcorder and a monitor in your garage or other large room. Recruit a friend or family member to sit in as your subject (tell them to bring a good book). Try different numbers of lights, different placements, different distances, different diffusion materials, different reflectors; experiment with any variables you can think of. Roll tape as you complete each setup, speaking aloud the details of that specific lighting arrangement. This will allow you to watch the tape later, gleaning even more from the experiment. If your assistant is willing, add a bottle of sunscreen and some sunglasses to your equipment list and repeat the experiment outdoors on a sunny day.

After a few hours of experimentation, you’ll know much of what the pros know about indoor and outdoor lighting. More importantly, your video will look more like the work of a professional and less like that of a lighting rookie. With that, let’s delve into the mind and method of the lighting professional.

General Lighting

The lighting professional knows that light operates in a set, predictable fashion, and every lighting technique follows a few key laws. Luckily for us videographers, light is a creature of habit.

Light and Distance

Perhaps the most important facet of light behavior is the dramatic effect distance has on light intensity. Light travels outward from its source in the shape of a sphere (or a section of a sphere). The light energy is distributed across the surface of this sphere, a shape whose surface area is squared each time its radius is doubled. This tells the lighting pro that light intensity doesn’t just drop to a half when she doubles the distance between light and subject, it drops to a quarter. If she moves the light three times as far, the light intensity drops to one-ninth. We call this the inverse-square law (see figure 1a).

In practice, understanding this rule makes it easy to predict the effects of light-to-subject distance. To cut light intensity in half, you need to move the light roughly 1.5 times as far from the subject. To bump intensity up by a factor of four, you cut the distance in half. Physically moving lights is the easiest way to control their intensity, and you don’t have to go far to make a dramatic change in the image.

Straight Lines

The other rule the pro builds her craft on is that light travels in a straight line until it’s absorbed or bounced in another direction. Understanding this rule opens up countless options for controlling light by bouncing it, blocking it, diffusing it and scattering it. Like a billiard ball careening off a bumper, light reflects off an object at the same angle it struck it (see figure 1b). The lighting pro relies on this principle to "recycle" otherwise wasted light and bounce it back into the scene with a reflector. So can you.

How Much Light is Just Right?

The lighting expert understands that poor images lie on both ends of the brightness scale. Too little light, and images suffer from drab colors and excessive video noise. Too much light, and images can look flat and washed out. Lighting newbies will learn soon enough that lots of light is not the same as good light.

The perfect amount of light gives the camcorder ample illumination for vibrant colors without flooding the whole scene. Indoors, this usually means putting up a few thousand watts’ worth of supplementary lighting. Shooting outdoors during the day, this means taming (or avoiding) the intense light of the sun.

Manufacturers frequently claim that their camcorders can capture images in very low light. The low-light ratings, given in lux units, represent the bare minimum illumination required for the camcorder to register some sort of grainy, barely recognizable image. Camcorders actually require lots of light–several hundred lux–to capture good noise-free images. Knowing this, you should bring indoor light levels up a few notches from those of the normal household bulbs. Bouncing a 750- or 1000-watt light off a white ceiling is a quick, easy way to bring up ambient light levels. From there, you can begin adding additional lights where needed.

Monitor Your Lighting

The lighting expert rarely works without a carefully set-up color video monitor. It allows her to keep an eye on white balance, color saturation and color accuracy. Some professionals go so far as to bring a waveform monitor to the set when lighting, checking their brightness levels and contrast with a high degree of accuracy.

A professional video monitor is not a must; virtually any consumer television or monitor with video inputs is a great asset when lighting a scene. The main benefit lies in the fact that the TV or monitor is a good representation of how your viewers will eventually see your work; a viewfinder is not. To mimic the pros, find a TV or monitor that you can trust and use it every time you light.

Camcorders with built-in LCD monitors offer the advantage of displaying color, but they’re not a very good reference when lighting a scene. LCDs display brightness and contrast quite differently from CRTs, and they don’t give you an accurate representation of how your lighting will look on a standard TV.

Too Much Contrast

Contrast ratio is the difference between the brightest and darkest image areas a recording system can successfully handle. Video can handle roughly one-eighth the contrast range of the human eye. This means a scene that looks just fine to the naked eye could contain considerably more contrast than video can handle. The end result is overexposed light areas or pitch-black dark areas.

Lighting for video is all about controlling contrast, usually reducing it considerably to get a good video image. The concept is simple: reducing contrast means throwing more light on dark areas, less light on bright areas, or both. The lighting pro has several options at his disposal to accomplish this. To flood more light into dark areas indoors, he can increase the wattage of existing bulbs, add more lights or change their positions. Outdoors, bouncing sunlight with reflectors works well.

Reducing the intensity of bright areas indoors usually involves moving lights back, using lower-output bulbs or adding diffusion or neutral-density gels to existing lights. Outdoors, the main culprit in too-bright video is the sun. Using diffusion between sun and subject drops light intensity dramatically, as does the most obvious solution of all–moving the subject into the shade.

Too Little Contrast

The lighting pro knows that low-contrast lighting makes for flat, boring images. Her goal is to bring contrast down to a usable level for video, while still using as much of video’s narrow contrast window as practical. Good video lighting usually has both strong bright areas and intriguing dark sections.

Indoors, this often involves raising the overall light level of a scene, then systematically adding contrast back in by creating or emphasizing dark and light areas. A pro creates dark areas by purposely blocking light from hitting that area, or by relying on the natural fall-off of light intensity due to distance. Bright areas are easy enough to create by putting up a new light or positioning an existing light closer to an object or surface.

Too little contrast is rarely a problem outside, though flat lighting can result from shooting on a very gloomy, overcast day. If forced to shoot in such a situation, the lighting pro may supplement daylight with artificial light. If things aren’t too overcast, reflectors can help bring up light levels to create highlight areas.

Mood Lighting

The lighting pro understands that even within the seemingly narrow confines of video lighting, there’s still plenty of room to get creative. She also knows that one lighting approach isn’t right for every scene and every type of show. Lighting should match and reinforce the mood of the scene, be it somber, happy, mysterious or romantic.

Lighting styles generally fall into two categories: high-key and low-key. High-key lighting is generally quite bright, with little contrast and few dark areas. Game shows, talk shows and sitcoms tend to use high-key lighting to maintain an energetic, "up" mood. Low-key lighting often has more contrast, with more shadow areas and less overall brightness. Dramas, horror movies and reality-based shows often use low-key lighting to convey a moody, dark feeling.

You can learn to match your lighting to your video as well. Simply keep each scene’s overall "mood" in mind while you’re setting up your lights. For low-key lighting, don’t be afraid to let a few areas of the screen get reasonably dark. For high-key lighting, get light levels up across the whole shot and eliminate most dark pockets and shadows. Neither approach requires an expensive lighting rig–you can achieve high- or low-key lighting with just a few lights, even those you find at your local home improvement store (see "Pro Lighting on a Low Budget" sidebar).

Indoor Lighting
Lighting for indoor shooting poses its own special set of unique problems, and lighting professionals know the solutions.

Controlling Indoor Light
It’s common for professionals to shut off all existing lights in a room and rely on their own instruments exclusively. Sometimes, such as when there’s no supplementary lighting hardware available, the pro has to use existing light to his advantage.

Often, he’ll get overall light levels up in the room by turning on every light. Since lamp shades reduce light output considerably, he may remove them altogether. Swapping a 40-watt bulb with a 100- or 150-watt variety will also provide a noticeable increase in intensity. He may fashion reflectors from cardboard, cover them with aluminum foil and place them near the bulb to intensify the light. If a lamp is going to be visible in the scene, there’s a good chance the light will be too bright for the shot. Putting a gray gel or other partially-opaque material inside the shade can dramatically cut down on excessive light levels.

The lesson for the home videographer is that, in general, it’s much better to give the camcorder lots of light than to give it too little. Household lights are perfectly useful for video, their main drawback being their relatively low output. Placed close to the subject, however (remember the inverse-square law), they can provide ample illumination for good images.

Color Temperature Matters
Every type of light source, be it midday sun, standard tungsten light bulb or professional quartz-halogen instrument, puts out a slightly different color of white light. We call this color temperature, and measure it in degrees on the Kelvin scale. Higher color temperatures put out a more bluish light, while lower ones are more orange-red. If you mix different types of light in one scene, color accuracy can go out the window. Pros know the color temperatures of various light sources, and they know how to shift them so they all match up.

Indoors, color temperature quickly becomes an issue if you’re trying to mix any combination of standard household bulbs, professional or shop lights and sunlight. If you white balance for household lights, professional and shop lights (both quartz-halogen) will put off a bluish cast, and sunlight will look even bluer. White balance for quartz-halogen: household-bulb light will look yellow; sunlight will look blue. White balance for daylight: quartz-halogen light looks yellow; household bulbs even yellower.

Home videographers must always be aware of the effects of mixing various color temperatures. Sometimes, it’s best to shut off a given light if it doesn’t match the color temperature of the others. Other times, a slightly mis-matched color temperature can be a desirable asset. If you light your scene with quartz-halogen bulbs and white balance accordingly, the lower-temperature home bulbs will cast a warm, yellow-orange glow.

Outdoor Lighting

Like indoor lighting, outdoor lighting has its own brand of complications. The main culprit? The sun itself.

Harnessing the Sun

The great light source in the sky is also the greatest challenge in outdoor daytime video. Our sun is incredibly bright, and its great distance from us qualifies it as a very small light source. This makes it throw harsh, dark shadows and reveal even the tiniest flaws in surface texture (or skin).

When possible, the professional will avoid shooting in the direct sun. He’ll move the action into the shade of a tree or building, or he’ll create his own partial shade by placing something between his talent and the sun. His main goal is twofold: reduce the intensity of the sun and make its light less harsh. Using diffusion netting accomplishes both, provided he can acquire a large enough swath to cover his subject from outside the frame. Some pros carry large frames they can erect over their subject or talent, effectively reducing the sun’s intensity and diffusing its harsh light. If he can’t erect a frame over his talent, the lighting pro will at least use a reflector to bounce sunlight into the harsh shadows on the dark side of the face.

Home videographers who are handy with lumber or PVC pipe can make their own portable frame, covering it with mosquito netting or the partial-shade fabric used in some greenhouses. If this is beyond your means, you can always fashion a reflector to eliminate harsh shadows when shooting outdoors.

Bouncing Light
As we’ve already said, reflectors are a great asset when lighting outside. The pro knows that few lighting instruments can keep up with direct sun when it comes to intensity. If a given outdoor scene is suffering from deep shadows, throwing up a light probably isn’t the best solution. For one, there may not be power where she’s shooting. Second, the light will need a blue gel to match daylight color temperature, which will cut down on its intensity (which was probably inadequate to begin with).

Enter the humble reflector, with all its many advantages. She can use it to bounce sunlight into dark areas even when there are no outlets handy. If it’s pure white, it generates no color-temperature shift. Because it’s usually fairly large, it softens the otherwise harsh sunlight as it deflects it. Reflectors are light and easy to pack, and they’re rarely very expensive. Reflectors can even give her more artistic control, as they come in various surface styles and colors: white (for a soft bounce), shiny silver (for a more intense, focused light) and shiny gold (for a warm, golden hue).

Home videographers can enjoy the benefits of the reflector with almost no capital outlay. Foamcore board, as found at art supply stores, makes for light, cheap and easy-to-shape reflectors. Cardboard is useful as well; you can cover it with silver or gold aluminum foil, white construction paper, or a patchwork of foil and paper. White auto sunshades work great as reflectors, and many will collapse down into a very small package.

Be Your Own ProGood video lighting is not brain surgery, and it doesn’t require a lot of sophisticated or expensive equipment. Lighting professionals rely on their knowledge of a few key principles of light, some simple tools and lots of experience. All three of these elements are within your grasp, if you take the time to learn and experiment with your lighting.

Maybe it’s time you became a lighting professional.

Contributing Editor Loren Alldrin is a freelance video and music producer.

SIDEBAR

Pro Lighting on a Low Budget
Lighting is one of the few aspects of video production where budget has relatively little impact on the final results. Light from a cheap lamp performs exactly like light from a designer lighting instrument, and the camcorder can’t tell that light is bouncing from a car sunshade instead of an expensive reflector. Pros know this as well–that’s why you’ll find many cheap solutions in their lighting kits.

Here is a list of inexpensive lighting products that work well for video production. These tools may not give you as much control as you would have with professional equipment, but they won’t empty your bank account, either.

• Quartz-halogen shop lights These lights are available from 250 watts all the way up to 1000 watts, and will set you back less than $20 a piece. Some come with stands, making them all the more handy for video lighting.
• Car sunshades These are available in basic white or silver; the really handy ones offer one side with each surface. Most sunshades fold up accordion-style or twist into a small circle. The latter is better, as it’s hard to get the accordion-folded shades perfectly flat during use.
• Foamcore This lightweight, easily cut artboard is a videographer’s best friend. You can make it most any shape and size you want, and it’s cheap enough to throw away without regret. You can cut interesting patterns in foamcore to shine light through it, splashing color and shape on a background surface.
• Cardboard Like foamcore, cardboard is useful for making "cookies" to shine light through. Covered with white or silvered paper, cardboard makes an effective disposable reflector.
• Bed sheet A thin bedsheet makes a great diffuser. Hung in front of a window or lighting instrument, a sheet will give you soft, diffused light well-suited to shooting human subjects.
• Diffusion netting Used primarily in gardening, this fine netting tames harsh sun better than an overcast day. With a little ingenuity, you can figure out how to suspend netting almost anywhere outdoors.
• Torch-style quartz lamps These tall, slender lamps fire light directly up into the ceiling. This creates nicely diffused light, which is perfect for raising the overall illumination level in a scene. Usually priced around $15, these lights look nice enough to have visible in the background of a living room or office scene.