When working on a lightboard, you need to be mindful of reflections. At the same time, often studios will have a relatively bright confidence monitor or teleprompter near the camera, and that produces reflections off a lightboard that are visible to the camera.
A trick to knock that out is to use a Circular Polarizing Lens filter, typically just referred to as a CPL filter.
CPL filters are polarized filters that take advantage of the fact that the light coming out of most LCD displays is polarized. If the LCD display is polarized, it's reflection off the glass and back at the camera will be largely polarized as well.
Be mindful - while all confidence monitors included in our studio packages have been tested to ensure they are compatible with CPL filters, some LCD monitors include diffuser lenses that depolarize the light coming out of the monitor, and prevent the CPL filters from eliminating their reflection. Unfortunately, you won't find this specification in manuals or online specifications.
If buying your own confidence monitor, we'd recommend buying a CPL filter first and testing monitors in person before buying. Look through the filter from the side with male threads. CPL filters are directional meaning the effect will not be seen from the opposite side. When you look at a monitor, rotate the filter and see if there is a position that fully blocks out the screen's visibility.
Above inexpensive consumer-grade cameras, most video cameras will have a threaded ring in front of the lens for the installation of filters. The compatible filter size will be listed in the specifications and manual for your camera.
Once you have your CPL filter and monitor, install the CPL on the front of your camera. Part of the filter will remain free to rotate. Rotate the filter to the position which minimizes the visibility of the monitor's reflection.
If you can still see a minor remnant of the reflection, you can then turn down the monitor brightness and contrast as needed.
Want to learn more about lightboards? Check out the rest of our lightboard resources.