To continue the discussion on studio lighting, let’s get into continuous light sources. With the new prevalence of digital cameras that include video capture, this type of lighting has seen a strong resurgence in popularity. While there are a few limitations in using a continuous light source (see Right with Light, part 6) this type of lighting can offer a lot of creativity to your work.
There are many types of light in this category, and, as with most photo lighting gear, there is a range of prices, types and quality. Unlike strobes, continuous lighting comes in many color temperatures, the most common is tungsten or about 3200K-3400K. This lighting is akin to the incandescent lighting in your house. This type of light has been the mainstay for most modern photography and is the generally the least expensive.
In the late 1960s, the HMI light appeared on the scene. Without going into the technical details, these lights produce a color close to daylight or around 6000K. The HMI was mostly developed for the TV and film industry to balance lighting while on location. I’ve used these in conjunction with strobes many times (this was a “style” I offered years ago). The drawbacks include the cost, inconvenience (they require a ballast to regulate the power), finickiness, and their tendency to drift in color as they age.
Florescent lighting has been the mainstay for most offices and a hassle to photographers for many years. Over the years, florescents have evolved both for the office and the home. Through internal filtration and construction, the color temps range from cool white, 4200K to warm white, 2800K. In recent years we have seen these evolve into compact florescent lights (CFLs), which are the leader in the green movement as they last much longer and require less energy to operate. For photography this has had a very positive affect in the form of a day light-balanced versions around 6000K with the wattage that allow them perform well. Many TV studios are moving in this direction. CFLs reduce the heat generated in the studio and help studios save in AC bills, not to mention time spent in makeup for the stars. We have recently started using a 900 watt daylight balanced CFL when we go to a location video shoot in an artist’s studio. It helps us balance our set with the existing daylight from the windows.
The other light that has seen recent growth in conjunction with digital photography is the LED. Over the past few years there have been several breakthroughs applied to photography and video with success. I feel that LEDs need more research and development to become a viable alternative. At this point the costs are high relative to the light output. I took as calculated plunge last year, with a two small battery powered units with limited success. For ENG work they performed OK, and on location in for a macro shoot they performed well as an alternative to flash units. Both florescent and LED are in the mid to high price range, but they last a long time and won’t require constant replacement as their predecessors do.
As you can see, there are alternatives to using a flash. At this point none offer all the same advantages, but they are catching up.
Questions or comments are always welcome, so speak up.