Expert Lighting Tips
Lighting is a language that can convey mood, time and style. Speaking in this language means taking control of the way your subjects are lit, either by manipulating the angles and intensities of the sources of light, adjusting the position of the object, or both.
For many video makers, lighting concerns are limited to guaranteemg the viewfinder’s low light warning indicator doesn’t start flashing. This attitude may be fine for casual travel and family videomaking, but it is careless in professional work.
Put simply, ignoring lighting means playing Russian Roulett with picture quality. You’ll also miss the opportunity to make your subjects and shots look their best.
If you pay no attention to lighting you may still obtain reasonably acceptable results, but on occasion the picture will he quite poor. A face may appear completely in shadow, or the light from a window will darken an entire room.
Most camcorders feature a backlight compensation control to adjust for this specific situation, but the use of such a tool should be considered a last-ditch effort. Hitting the backlight button, or opening the iris, represents a quiescent acceptance of light as it is.
This article is about what you should do long before you ever think of hitting the iris control. Rather than merely accepting a given set of circumstances, we’ll first describe the ideal lighting situation. Then we’ll examine how this model can be applied to real world low budget videomaking.
You should exercise as much control as possible over the light. Outdoor lighting has one big advantage-there’s plenty of it. But it’s largely controlled by nature, and will rarely heed your command.
Indoor lighting allows for more precise control and consistency.
A subject bathed in light falling equally from all directions will look flat and uninteresting. Flat lighting is merely adequate: faces are illuminated, but don’t look their best.
Flat lighting is usually necessary when a large group of people must be lit, but take more care to light an individual. Do not illuminate the face evenly. Instead, focus different lights onto the subject from various angles and intensities.
The most common approach to studio lighting is three-point lighting, so named because three different lights are placed around the subject.
The strongest source of light is called the key light, typically placed about 45 degrees horizontally off center. Vertically, the key light is also usually about 45 degrees up from the subject. The key light will typically illuminate one side of the subject’s face more than the other.
The second step in the setup is the fill light. As its name implies, the fill is meant to fill in shadows created by the key light. It’s located on the other side of the face from the key, dimmed to half the key’s intensity. This intensity adjustment can be accomplished with a bulb of lower wattage or by moving the light further from the subject.
With the latter, remember that the intensity drops off in proportion to the square of the distance-that is, doubling the distance between the light and the subject will produce only one-fourth the illumination shed in the original position.
A Light for Every Position
Ideally, specific lighting instruments will be used for each type of light.
A directional spotlight is often used for the key light. It projects light through the single focal point of its lens. Fill light requires a more diffuse source. This can be generated by bouncing the light off a reflector such as a white ceiling, reflecting umbrella or a simple white card. You could also de-focus light by passing it through diffusion material like spun glass, tracing paper or heatproof opalescent plastic. The result is known as soft light, as it doesn’t create the harsh, hard-edged shadows thrown by point-source light.
This key/fill arrangement mimics the arrangement of nature, where the sun acts as a point source to illuminate one side of the face, with the sky filling shadows with softer, diffuse light.
The third component of the three-point lighting setup is the backlight, located behind the subject, usually high above, pointing down and slightly forward.
The purpose of the backlight is to highlight the top of the head, create bright points in the hair and separate the face from the background.
The backlight is typically two times brighter than the key. Because it’s pointing downward, most of the light does not actually illuminate the subject. When working with low ceilings it can sometimes be tricky setting up a backlight so it isn’t shown in the frame.
A barndoor attachment to the lighting instrument can help prevent the light from spilling into areas where it shouldn’t be. This is particularly important when lighting more than one subject simultaneously.
The three-point lighting plan is the norm for talk shows, news desks similar studio productions with no pretense to realism. The studio lighting scheme is simply designed to make people look their best.
In dramatic productions, however, credibility must be considered. The lighting scheme must make the set look real and support what it suggests. If there’s a window in the room and the scene takes place during the day, the key should shine from the direction of the window.
Whenever a light becomes part of the set and appears within the frame, it’s called a practical light. In some cases a practical light is actually used as one component in the lighting scheme, but more often it simply serves as an apparent source of light.
If you use a practical light bright enough to illuminate the subject, it will saturate the camera beyond its maximum white level.
Installing a lower wattage bulb makes the lamp look more like a normal part of the set. Then you must illuminate the subject using a different, high-powered lighting instrument, placed offscreen and aimed from the same direction as the lamp.
The Light Kit
Many professionals carry three-light kits for basic field setups. These kits typically consist of three lights, three light stands and attachments to hold accessories like barndoors and scrims. Some kits include reflecting umbrella attachments.
Photoflood bulbs in clamp-on reflectors are a low-budget alternative to professional halogen lamps. The bulbs are available in professional photo supply stores; the clamp-on reflectors can he found in hardware stores.
When using lights mounted on stands you can create a sturdy setup and prevent accidents by following this sequence.
First, assemble the stands where you want the lights. Extend the legs, using the thickest poles possible. Next, affix the lights to the stands; then add the attachments to be used. Finally, plug the electrical cord into the light, using gaffer’s or duct tape to secure wires.
Running a three-point kit requires a lot of electrical power. A typical kit consists of three halogen lamps, each using 1000 watts of power-three thousand watts total.
Most home wiring can’t handle a 3000-watt load on a single branch circuit. Fortunately houses and apartments usually have a number of branch circuits. The trick is to spread the lights among several. This will often require heavy-duty extension cords to link the lights with outlets in faraway rooms.
Each branch circuit has its own circuit breaker or fuse. You can determine which outlet is part of which circuit by individually tripping one breaker at a time, plugging a lamp into each outlet to watch where it won’t work.
The breaker for each branch is labelled with a maximum number of amperes, or amps. You can convert between amps and watts using the following formula: # of watts = # volts x # of amps.
In the U.S., where household voltage is usually around 115 volts, the formula becomes: # of watts =115 x # of amps, or, expressed to calculate amps, # of amps = # of watts 115.
Using this formula, it can be seen that to run 3000 watts of lights on one circuit requires a capacity of at least 27 amps.
Since most household circuits boast but 15-amp capacity you’ll need to put each light on a different branch circuit.
Of course the easiest way to avoid electrical problems is to use battery-powered portable lights.
Most of these units run ten to fifty watts. A built-in rechargeable battery usually supplies the power, except on some low-powered lights supplied with certain camcorders. These last run off the camcorder battery. The amount of time you can use the light before recharging is typically 15-30 minutes.
Most portable lighting devices mount directly atop the camcorder. This is convenient for handheld operation, but far from ideal for optimum lighting. Best is maneuvering the portable light into a position similar to a studio key-up and off to one side. This is especially effective if the other side of the face receives fill light reflected off a wall or ceiling.
One compromise is to keep the light mounted on the camcorder, but pointed up so that it bounces off the ceiling and illuminates the face from above. This technique is called bounce lighting. To be effective, the ceiling must be reasonably low, and white or a very light color. The lamp should be fairly powerful since its light will lose much intensity in the bounce.
In the field you will rarely use your portable light as the only source of illumination. At the location, you will usually find some indoor or outdoor light that can help. Depending on the type and intensity of the available light your camcorder light might serve as the key light, as the fill or even as the backlight.
The Color of Light
Different lights have different color temperatures. Each requires a speciic white balance setting. White light consists of a mixture of all the different colors in the spectrum; color temperature describes which colors are dominant in the mix. The camcorder’s white balance adjusts to compensate for these differences.
Most lights designed for videomaking feature a color temperature of 3200 degrees Kelvin, the so-called “tungsten” light setting. The bulbs are specially designed so that even as they get older the temperature won’t change much.
When you mix different types of light, the camcorder can adjust for only one. For example, if a face is illuminated by outdoor light on one side and indoor light on the other, one of two problems will occur. Either the indoor portion of the face will seem normal and the outdoor side appear blue, or the outdoor portion will look normal and the indoor glow red. If the camcorder’s automatic white balance is enabled, the decision will be determined by which type of light fills most of the picture.
Since most camcorders feature black-and-white viewfinders, casual videomakers generally don’t recognize this mixed lighting muddle while they are shooting. In black and white the different colors of light blend together harmoniously. Later, when viewed on a color screen, the results are often disheartening.
The best way to avoid mixed light problems is to choose just one type of light and eliminate the rest. If you must use mixed light, select one type as dominant and manually set the white balance accordingly.
In Hollywood translucent colored filters made of plastic film or gelatin arc used to convert one type of light to another. Orange sheets taped around windows convert outdoor light to tungsten color temperature. A blue filter over an electric tungsten light creates a color temperature similar to outdoor lights.
The ideal orange is Wratten 85, the best blue Wratten 80B. Both are available at professional photo supply stores.
A low-budget alternative involves obtaining a sample of the ideal color, then purchasing a sheet of similar color from an industrial plastic supplier. No matter how good a bargain you find, it will still take a lot of time and trouble to properly tape a window with filter film. It may also require a lot of camera angle adjustment to obscure artificial light reflections.
Reflections and Effects
An inexpensive tool for working with available light is the reflector.
Professional reflectors use a shiny silver-coated plastic to maximize reflection, but a low-budget reflector can be as simple as a large white card or foam core art board.
On sunny days, one side of a person’s face may be harshly illuminated while the other is unnaturally dark. Or a long shadow from the nose may streak across the face. Holding a reflector just off camera on the dark side of the face will catch the sun and reflect it back, creating the effect of a fill light.
Beyond the basic three-point lighting scheme, there are a host of creative lighting effects that help create a specific mood. Perhaps the most recognizable of these effects is the venetian-blind lighting technique that characterized film noir thrillers of the forties and fifties. The stripes of light resulting from illumination passing through the blinds create a feeling of tension.
A single light used without a fill can create a feeling of intensity. Using a single light from the far side of a face, so that most of the face is in shadow, presents a sense of intrigue. Lighting the face from underneath can turn even grandma into a ghoul. A flickering candle bathes a scene in romance.
So far, we’ve only discussed lighting the subject. In low-budget videomaking this is usually the prime concern, but as productions grow more sophisticated the desire to light the setting becomes equally urgent.
A newscast provides a simple example. In addition to using key, fill and back lights on the anchor, the background must also be lit properly. In the simplest set designs, the backdrop might consist of nothing more than a blue wall; the goal is therefore to evenly illuminate the entire background. One or more soft fill lights works best.
A more expensive set may show newswriters and editors in the background; the lighting here must be carefully designed so they’re evenly illuminated. If there are TV monitors on the set, studio light reflections must be eliminated from the screens.
These tips are just guideposts for your own experimentation. Innovative videomakers will find that lighting is one area where you don’t need a lot of money to get the job done right.
Your most important equipment is your eye-brain system. As you approach each shooting situation, look upon the lighting as a unique challenge. Whether equipped with a professional lighting kit or a battery-powered portable with a cardboard reflector, study the scene and set your lights so your people look as good as can be.
Don’t just see the light. Take control of it.
Cliff Roth is a Videomaker contributing editor.