How to Work With On Site Fluorescent Lights When Lighting for Digital Video
Lighting for Digital Video
Fluorescent lights are the worst enemy of a cinematographer. They have a greenish tint built in that brings out a bland and often annoying color in the subjects it lights. It is easy and cheap for many locations to use them in general so as to get blanket lights on everything, but they really are not optimum for making things look good in any situation. When you are filming on location with florescent lights you have a few choices ahead of you to decide how you want to deal with them so they do not disturb your lighting.
Turn of the Fluorescents
For smaller locations the first option is always to turn off all of the florescent lights. This is possible only when the area you plan on filming is small enough to light effectively with your own lighting equipment. If the location you are filming is important for the film space, such as making a grocery store still appear like a real grocery store, you may have to mimic the position of the overhead florescent lights. To do this you just want to get higher wattage daylight balanced lights to point at the ceiling or a top hanging reflector cards. Even a large HMI will be perfect for this situation. Once you have mimicked that soft light from the florescent bulbs you can do more detailed lighting on the subjects with your strategically placed smaller light kits.
Replace the Lights
If you need to light a larger area you may just need to keep that light in place. If you are getting more than just the immediate scene in the frame, if you have to move quite a bit, and if your light kits are just not replicating the blanket of light overhead you may want to try to replace the bulbs. This is expensive and time consuming, but does solve the problem pretty clearly. You investigate exactly what type of fixtures they are in and then order daylight balanced bulbs that will fill their spots. You then simply go in and replace all of these lights one by one.
Gel the Lights
A more practical way of maintaining the overhead lights without replacing bulbs is to simply mimic the green content of the florescent lights on your lights, then white balance out the green. Using a color meter you can measure the amount of green that is falling on the subjects and objects from the florescent lights. You then begin adding thin eighth strength green gels to all of your lights. Measure the color temperature that is coming off of them and when you get close to the color temperature of the overhead lights you will be generally ready to go. Now you simply white balance in the green tinted area and then all of the green color will be taken out of the image. What you have done is essentially made all your lights to contain the same florescent green then you have identified and abolished it in your camera. This is fairly standard on most sets in large supermarket or ‘big box’ store settings and means that you can continue to bring only a small light kit with you when in production. You will also have to note that you may have to use stronger lights as the green gels will reduce intensity somewhat.
