Today, most commercial locations such as office buildings, supermarkets and shopping centers use fluorescent lighting. As a director of photography, planning a location shoot will require knowing how to best deal with fluorescent lighting. The difficulty which fluorescent lighting presents is that fluorescents emit high green color spikes. While our eyes adjust to the green color which fluorescents emit allowing us to see it as white light, film or video do not. You will need to color balance the video for the green, add a minusgreen filter to the lens or time out the green during the film development process. The problem is that often times just using the practical fluorescent sources will not be enough to produce a favorable image because either the image will be too flat or the fluorescent sources do not provide enough light for proper exposure. The solution would be to add other light sources to the set. Once mixed color lighting is introduced then the light sources must be balanced to the same color spectrum or your image will have an unattractive green color hue to it.
For the purpose of this discussion, let us use as an example an office space with fluorescent lighting recessed into the ceiling and the introduction of another source of light. Listed below are two scenarios for balancing florescent lighting with either tungsten or daylight balanced sources.
Scenario 1: Introducing Tungsten Balanced Lighting
To balance for tungsten light sources gel warm white fluorescent bulbs with minusgreen, gel cool white fluorescents with fluorofilter or replace the regular fluorescent bulbs with full spectrum fluorescent bulbs such as Optima 32s. Plusgreen 50 can also be added to tungsten light sources to balance the source to cool white fluorescent bulbs but the green color will need to be removed by adding a minusgreen filter to the lens or timing out the green during the film development process.
Scenario 2: Introducing Daylight Balanced Lighting
To balance for daylight add minusgreen gel to the fluorescent bulbs or replace regular fluorescent bulbs with full spectrum fluorescent bulbs such as Optima 50s. Plusgreen gel can be added to windows or HMIs to balance it with the fluorescent bulbs but the green will need to be removed by adding a minusgreen filter to the lens or timing out the green during the film development process.
To color balance locations lit by fluorescents it may take a combination of these techniques. The location will dictate the best course of action. If you are filming in a small office it might be better to gel the fluorescent bulbs to match the tungsten or daylight sources. If you are filming in a large supermarket with many fluorescent sources it would be a lot easier to gel the tungsten or daylight source to match the fluorescents.
Saro Varjabedian is a director of photography based in New York and has worked on over twenty films, music videos and corporate videos for various production companies. He has recently finished production on Erza, Story 353, Agoraphobia, Hero the Great, and the TV pilot, Power-Outage.
