First of all, you must decide what types of lights to purchase. There are two basic types: Tungsten or Strobes. Tungsten lights are continuous photofloods, which tend to generate a lot of heat. Strobes are flash units. I personally use strobes and really like them. More specifically, I use the Alien Bees B800’s. I love these lights and find them really easy to use. Your strobes will come with something called a “modeling light.” This modeling light is there to allow you to see where your light will be. It goes off when you fire the strobe, and comes on again a second later, letting you know that the strobes are ready to be fired again. The modeling light gives off very little heat compared to the tungsten lights.
Whatever brand you decide to purchase, make sure that they will allow for lighting accessories such as softboxes and umbrellas, barndoors (plates that attach to the front of your lights) and snoots (a long tube – most often used as a hair light). These accessories enable you to control where the light goes. The manufacturer of the lights you choose will more than likely also sell light stands, which you will also need.
You can get started with as little as one light, but make sure that you have some sort of reflector to provide fill light. Reflectors are available from professional camera shops (online or off), but a large piece of white foamboard or cardboard will do the trick as well (and is much less expensive). After your business gets going and you can afford more lighting, you can add a fill light, a hair light and some background lighting as well. You will need umbrellas or softboxes to go with your main and fill lights.
Main Light: The primary lighting
Fill Light: Fills in the shadows created by the main light
Hair Light: Separates the hair from the background
Where should you place your lights? Generally speaking, the closer the lights to the subject, the more harsh the lighting. The further away you place your lights from the subject, the more diffused the lighting will be. When using my main light with a softbox, I generally place the main light approximately 4 to 5 feet away from my subject (slightly above the subject’s eye level) and off to the right of the camera. I place my fill light slightly further back (on the subject’s eye level) and on my left. Remember, your subject should be at least 4 to 5 feet away from the background to reduce shadows. If you are using a hair light, it should be above and behind the subject’s head…but experiment with it to find the placement you like best. You will definitely need to use either barndoors or a snoot for your hair light to keep it from shining into the camera’s lens.
For portraiture, you will want to use a lighting ratio of 3:1, meaning that your main light is approximately 1-2/3rds f-stops brighter (or stronger) than the fill light. A 2:1 ration means that your main light is 1 stop stronger than the fill light. The hair light should be one stop stronger than your main light. The same goes for background lighting if you want a bright white background. This is another reason I like my alien bees so much: they are really easy to adjust. You can simply move a switch on the back of each light to set it, and it is easy to get that 3:1 or 2:1 ratio. You will want to keep the room lighting (table lamps, overhead lights, etc.) to a minimum.
For my set up (I use the Canon 20D and the alien bees B800’s), I set my camera to 250 and 13, my main light at ¼ power, and my fill light at 1/16 power and I get great results. I would recommend just playing around with your settings until you find the ones that work.
We’ve covered the basics here, but you still may want to invest in a good book on studio lighting to further your knowledge.