For years photographers made portraits using photoflood, tungsten, quartz and other continuous light sources that fall under the general heading of “hot lights.” These light sources have some advantages over electronic flash: They can be inexpensive, let you see the light as captured allowing you to use your camera’s in-camera meter, and are generally smaller than studio flash units. Instead of the subject being distracted (or blink) from electronic flash, continuous light sources let them relax. On the downside, working with hot lights often creates problems because of their color temperature and they are, waddaya know, hot.
Most digital SLRs include settings for tungsten light and some will even let you dial in a specific color temperature in Kelvin. For the first shot, to try the camera’s Auto White Balance (AWB) setting. Many times this will produce spot-on color without any color temperature gymnastics. If all else fails, you can use the camera’s built in controls to create a custom white balance using a dependable “white” color source to calibrate your camera, such as Kodak’s Gray Card Plus that has a large 18% neutral grey area bordered by 3% and 90% black and white patches.
Hot lights come is several flavors including Photofloods, HMI, and Quartz and each system has its pros and cons. Photofloods are a simple combination of a housing, stand bracket, and reflector and use a incandescent bulb not much that different from the light bulbs in your lamps at home and are almost as inexpensive. A two light kit, such as Smith-Victor’s 2-Light Thrifty Umbrella Kit costs less than $150 and includes two 500-watt 3200K lamps, two 8-foot light stands, two reflectors and two 32-inch shoot-through white umbrellas.
When compared to incandescent, HMI (Hydrargyrum Medium arc Iodide) lights deliver five times the light output per watt and generate less heat. Unlike quartz the color temperature of HMI lights is the same as daylight and won’t require a tungsten color balance setting. Designed for the film and video industry, HMI is a flicker-free light source that’s also recommended for digital still photographs requiring long exposures. Unfortunately, they are pricey.
Between Photofloods and HMI is the Goldilocks of continuous lighting, the quartz light that’ available in sizes, shapes, and prices to suite almost everyone’s lighting budget. Quartz lighting fixtures use high-pressure incandescent lamps containing halogen gases whose filaments burn at higher temperatures with higher efficiency, producing more lumens per watt than incandescent. Quartz does not darken with age but gets extremely hot so be careful to avoid burnt fingers and let them cool off before touching one of them.