When our writers had a chance to see the CBL system at NAB this past year, there was a lot of speculation and general confusion about how it worked. Some thought it was designed to fit over the camera (like a popular competitor does) to record light. Others thought it was an actual lens for the camera that purified the light coming into the camera.
However, when CBL sent us a demo to try out for a review, we came to realize that this device is simpler than we had expected and more complicated than you might expect.
What the CBL system is, essentially, is a specially molded, circular white balance card which has been embedded with prisms. Zoom in with your digital video camera (or digital still camera), white balance on the card, and you will get a more authentic white balance than you could from a normal white balance card. This is because the prismic reflectors in the CBL permit a truer representation of the light that's in the environment you're in. This is especially helpful when you're in areas with mixed lighting, such as an indoor scene with both daylight and incandescent lighting.
The folks at CBL created this lens to allow you to accurately record a scene so that little (if any) post-production color correction is required. This is because, unless you're shooting in a RAW format that allows a lot of tweaking to be done without damaging the footage, any color correction will subtly degrade your footage. The more you have to do, the more degraded the footage becomes.
The CBL is pretty easy to use. Unlike most white balance cards which require you to put the card on your subject and then zoom in, the CBL allows you to simply put the card far enough in front of your camera to white balance. So long as you're in the same general lighting area as you will be for your shoot, the prisms in the lens allow you to get a natural, believable white balance. I used this extensively on a shoot I did this past month and found it to be extremely natural and easy to use.
