Let's talk gels.
I shoot in a hospital, and will be shooting a round of commercials later this month.
We have a newly expanded tungsten/daylight kit with Lowel/Kino/Arri lights. We'll be shooting mainly indoors in several locations throughout the hospital, with varied lighting setups.
My question is for the fluorescent ceiling lighting in a larger room setup. Having never used gels in a large room set, what gels should I look into and how have you used them in your experience?
My initial (and admittedly inexperienced) idea was to purchase a minus green roll from Film Tools and cut sheets to fit the insides of the fluoro units in the ceiling to achieve a tungsten color balance. But would this be 1/2, 1/4, 1/8? Is this line of thinking even a good one?
In addition, what other colors/NDs have you found useful for ambient/spot lighting in your experience?
I look forward to your insights. Thank you.
We've had this discussion a hundred times here on the lighting forum, so please feel free to check the archive, but the best, easiest and most elegant solution is to use 4' Kino's as flour lights and "poison" them with the same tubes as are in the ceiling. This way all the light is the same color. White balancing the camera will correct everything. The hospital engineering staff can provide you the same tubes from their stock or you can simply steal some from the ceilings that are not in play and return them later.
To finesse each particular shot you might consider turning off or flagging the ceiling lights just above your subject (in static shots) to eliminate the bright "top lit" nose effect.
You'll regret gelling tubes or tungsten lights to "match" because it cannot be done, and also it's a lot of timeconsuming work both to put up and take down. The fluorescents are "discontinuous" light sources, meaning they have "spikes" of green which can not be optically filtered out.
I understand that you probably do not have the 4' Kinos (Fourbanks and Twobanks are the best for this purpose) in the kit that you own, but they are inexpensive to rent (especially without tubes) and priceless for this scenario.
John is so right! The quickest, easiest solution is to use the same lamps on the floor as in the ceiling, and manually white balance. (If the resulting image looks too cool, white balance again, but this time place 1/8 CTB in front of the lens as you do. The camera will add warmth to compensate for the blue. Remove the blue once the white balance is done, and there are you with a warmer image.)
You don't say if your overheads are cool or warm fluorescents. Most likely they are cool, or roughly daylight balanced (with a green spike your eye can't see but the camera can.) That means that if you add any of your tungsten units to supplement the floor kinos with the same bulbs as the overheads, you will need to add to these tungsten units: probably 1/4 plus green and also 1/2 blue. White balance without these tungsten units turned on. Then turn them on, and correct the gelling as your eye sees fit. Be sure to have on hand some sheets of 1/8 and 1/4 plus green; 1/8 and 1/4 and 1/2 CTB.
The best way to scout would be to take along a 3-color meter and measure the amount of green/blue/orange in the existing fluorescents. Whatever the meter tells you you need to add to your tungsten units, do 1/2 that strength.
director of photography
San Francisco Bay Area
and part-time instructor lighting and camera
grad school, SF Academy of Art University/Film and Video
I remember reading that when they built the sets for "ER", all the ceiling units were made with kinos. Your budget won't afford that, likely. Rick and John have shown you the way and it is the most cost-effective and practical way to go.