Continuous lighting is always on, and the obvious advantage to working with continuous light sources is that unlike strobes and monolights, which take a great deal of practice to learn before you inherently understand what changes will look like in a shot, what you’re seeing in the real world with continuous lights will closely resemble the image that you’re capturing.
With continuous lighting, what you see is what you get, and that makes it simple to adjust light positions and output as needed. Historically, there were many downsides to working with continuous lighting, however—one of the reasons why strobes and flashes found such popularity. Continuous lights can be very hot, for example, which is a significant problem on closed sets. But the technology has improved to the point where these disadvantages have largely been eliminated. Now that video is included in most new still cameras, continuous lighting is once more finding itself ignited as a market, with several new available models and technologies, like LED lighting, that are revolutionizing the industry.
TUNGSTEN AND FLUORESCENT
The classic tungsten bulb is synonymous with continuous lighting. The historic bulb type is old technology, so it’s very affordable. Tungsten also produces a much stronger output over other kinds of bulbs, like fluorescent and LEDs, but also more heat, as well.
The color temperature of the light produced by tungsten is much warmer than the standard daylight output of flashes and most other bulbs, with most models falling in the red-orange range of 3200K-3500K. This means that you must white-balance correctly when using tungsten or your subjects will appear very yellow.
Tungsten bulbs that have been designed for photography and video have shorter life spans than most other kinds of bulbs, and their color temperature also makes them difficult to mix with daylight without a corrective gel. Fluorescent bulbs, meanwhile, are seeing a lot of use on sets, thanks to a soft daylight output that’s accompanied by a lesser amount of generated heat (though these bulbs can still get quite warm). The quality of the light is flattering for portraiture, but this type of lighting also can be limiting when looking for harder contrast in an image.
Modern LED lights are constant, dimmable and often color-adjustable for achieving both daylight and tungsten output from within the same fixture. Heat generation is extremely minimal to the point that it’s almost nonexistent, and LED bulbs also have much longer lifespans of thousands of hours.