Understanding as much as possible about the physics of light will greatly improve your skills as a cinematographer. I recommend reading Placing Shadows
The Arri kit provides great latitude in an easy-to-transport package. Recently I have also been utilizing china balls while on set. China balls are a great addition to your lighting package and they have several advantages. However, consideration must be given to the type of look you want to achieve before you decide to use them, because china balls aren’t right for every occasion.
The first thing to consider is the fact that the light coming from a china ball is difficult to trim. You’re dealing with an even and diffused light source, so you will need flags and c-stands to control how the light spills onto the scene.
Second, if you want to utilize a low-key lighting approach to your set, china balls are probably not the way to go. Since the light output is even, the contrast of the subject is reduced.
Third, china balls are difficult to gel. You can always purchase daylight balanced bulbs or tungsten bulbs to match the color temperature of your scene, but trying to color correct with gel is more challenging than using lamps with barn doors.
With these considerations in mind, china balls have some great advantages:
Light Output
China balls give you a nice, soft, diffused light source with little effort. If you want to achieve the same look with a lamp from an Arri kit, you would have to add a chimera, or diffusion, add some scrims, adjust the lens, etc. With a china ball, you can simply put it on the stand and plug it in.
Quick & Efficient
China balls are quick and easy to set up and use lower wattage bulbs. If you need to shoot a number of on-camera interviews during a grueling run-and-gun kind of day, a china ball is a great asset.
Comfortable
Since China balls use lower wattage bulbs, they don’t give off nearly as much heat as other tungsten lamps. Therefore, your talent can work under them for longer periods of time without getting too hot.
Affordable
Not everyone can invest in a Kino-Flo or Arri kit, but China balls are great because of their pricing and availability. No-budget filmmakers can grab a few of these lights, get out with their cameras and their friends, and shoot some great looking footage.
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