Photography Lighting Basics
In this article we’ll concentrate on Studio Lighting, although Natural Light and Available Light are also important to know.
Indoor photography is the bread-and-butter of many photographers. From wedding photography to advertising: from portraits to pet shots. A large part of the photographers work is done in the studio or other indoor locations. Artificial lighting plays a key role in indoor shooting. Unlike outdoor or available light photography, where the light is there and you decide how to use it, in indoor work you start by deciding what light sources to use and how to use them. You have a choice of two basic artificial light sources: flood or flash.
By the term flood, we are referring to continuous studio lighting. By the term flash, we are referring to virtually instantaneous lighting, electronic flash.
As we have discussed in the Introduction to Lighting for Photography article, light is light, whether it comes from the sun, a flood lamp, or a flash unit. But the quality of the light, it’s intensity, it’s duration, it’s direction, and it’s color, vary with it’s source. Each type of lighting can be right, depending upon the effect you want. So don’t fall in love with only one type of lighting. Learn to use them all, so that you can always choose the best light for the job.
Floodlights:
Let’s start by exploring the use of floodlights. We’ll take up electronic flash later.
For many years floodlights were the mainstay of the studio photographer. Today, most photographers have switched to electronic flash, but continuous-light floods are still used. They are the starting point for many looking to study photography lighting because you can see the lighting effect before you shoot, and because they are inexpensive and easy to use and control. Since you can see in advance exactly what you are going to get on your picture, you can easily move your lights on your subjects around to get exactly the effect you want.
A floodlight sometimes called a photoflood is a powerful incandescent electric light bulb that can work off regular household current. Similar to household light bulbs, they give off a far more intense light. Another type of incandescent continuous lighting you should know about is quartz-halogen lighting units. These are self contained lighting units that give of an intense light. They are compact and lightweight, but are more expensive than conventional photofloods.
Electronic Flash:
Now that we have talked about floodlights, let’s talk about electronic flash. Electronic flash is also called speed light, strobe light, or just strobe.
Let's start with the most important: Output power is measured in Watt-Seconds (WS). Watt Seconds are simply a measurement of the power and discharge capacity of an electronic flash's power. Other important considerations when evaluating different electronic flash units are flash duration and recycle time.
Some electronic flash units include a rating for a Guide Number (GN), which is a number that relates the output of flash. Guide Numbers are quoted in feet or meters, and are valid for a specific ISO speed. The higher the guide number, the greater the light output. Guide numbers serve as a way to calculate aperture when shooting flash in manual exposure mode. To determine the correct aperture, you divide the guide number by the distance of the flash unit--not the camera--to the subject. Realize that guide numbers are just that, guides. The exact amount of light that hits the subject depends upon many factors, including the normal variation of light output from flash unit to flash unit, the size of the room, the color of the walls and ceilings, and the tonal values of your subject. With all these variables, what do you do? Experiment!
Light modifiers:
Raw light from floodlights or electronic flash is seldom useable as-is. To make a portrait or shoot a product, you're going to have to modify the quality of that light. To produce a soft, less directional light than the raw light, you can use umbrellas, soft boxes and reflectors.
Today many companies offer lighting kits consisting of continuous lighting or flash units, umbrellas or soft boxes, light stands, reflectors, backgrounds and even a case on wheels for a single portable studio.
Light Meters:
You're also going to need a handheld light meter that can read flash output. Since most meters these days include a flash function, it's not as bad as you might think. Most cameras have built-in meters you can use for one or maybe a two light setup. With a multi light setup a light meter will be a valuable tool for you to own.
