The modern cinema and video industries are heavily dependent on lighting equipment. From high-caliber studio cinematographers to personal video enthusiasts, just about everyone uses extra lighting to create harmonious visual imagery. If you’re looking to light up your next production, or just interested in learning more about what goes on behind the scenes, this guide to the key light sources used in the business will help illuminate the way.
Hydrargyrum medium-arc iodide (or simply HMI) refers to the lamp operating by creating an electrical arc between two electrodes within the bulb. This excites the pressurized mercury vapor and metal halides and provides a very strong continuous light that’s been a favorite of filmmakers for decades. HMIs are a high-priced light source, manufactured by the industry giants, but are usually accessible to videographers through rental dealers.
A key feature of this type of light is that it provides a perfect daylight source balanced at 5500 Kelvin, allowing you to film daytime scenes around the clock — one strong HMI source can create the effect of a sunny day in pitch dark night. Typically, these sources also need to be powered through an electrical ballast to limit the current and provide precise voltage.
Check out this clip to see sunlight-like light generated by a 5000 watt HMI source:
Tungsten light is pretty much the same as the light bulbs we use in our homes — it produces warm, yellow light. In this case, luminance is generated by heating the wire with a passing current trapped inside a glass or quartz environment filled with inert gas. The problem with this type of light is its high consumption of electricity and very high heating. In almost all cases only, 5% of the energy used is transferred to visible light, while the rest is wasted on heating the wire. Tungsten is typically measured around 3200 Kelvin.
This type of incandescent light was heavily used in the early days of film, but is less and less popular today — modern video productions tend to use it only as a practical source of light (when lighting or illumination is the deliberate use of light to achieve a practical or aesthetic effect). On the other hand, tungsten light is affordable and probably enough to light a small scene when the action takes place in an interior environment. Check it out in this video:
A fluorescent light is a low-pressure mercury gas discharge lamp that uses fluorescence to produce visible light by heating up the phosphor coating inside. Fluorescent lamps also produce ultraviolet waves and are about 10 times more economic and ecologically friendly than tungsten light sources. Fluorescent sources are about the same temperature on the Kelvin scale as HMIs and often produce light equivalent to 5400 Kelvin. (They’re also available in a tungsten balance 3200 Kelvin.) Typically, these lights are used in major video and film productions pretty much anywhere cinematographers can’t use HMI sources, they rely on fluorescent lights. This type of lighting is very easy to use and provides a great cinematic lighting solution for challenging scenes and are the go-to light for interviews.
Light-emitting diodes (LEDs) are a two-lead semiconductor light source that has become very popular in recent years as the technology has become more affordable. These lights are extremely ergonomic and provide an eco-friendly alternative to filmmakers who want to stay mobile and lightweight with their kits. LEDs have useful features such as temperature control, battery powering, and compact design. Filmmakers can get a cool daylight temperature out of these devices, as well as cozy yellow tungsten light, just by controlling the dimmer on most of the devices. These relatively cheap, lightweight, and versatile lights are the lights of the present and the future.
Here is a quick video of an LED light-source in action:
Strobe lights use a xenon flash lamp to provide a burst of daylight-like flashes, heavily used in photography and commonly referred to as flash light. These sources are typically mounted on digital or film cameras, and the light bursts from them are matched to the shutter speed to light the scene when shutter opens, so that frame gets exposed to the light. Photographers use these sources to give extra light “kick” to darker scenes. One area of modern digital photography that almost always uses strobe light is fashion photography. Almost all the studio setups use larger strobe lights mounted on stands with heavy diffusions to create soft light that smooths out skin tones. Flash lights are also used in event and portrait photography and sometimes even in film and video productions.
In addition to these lighting solutions, natural daylight is also of course an option, but it’s far less under your control, as it leaves you subject to the forces of nature. What are your favorite types of lights to use? Do you have any other go-to options we didn’t cover here? Tell us in the comments!