Videography Tips and Techniques

Issue   1     Tip 3

White Balance

White balancing is  calibrating your video camera to capture color as accurately as possible. The idea is you tell the camera which color it sees is actually white, letting the electronics  adjust everything else using white as the base. We’ve all seen video that have not been properly white balanced. Example is  shooting outdoors, then walk indoors, the video may appear reddish/orange. If filming inside, walking outside may make the picture appear bluish or when videoing underwater and the video appears bluish. Almost monotone in color.
The color temperature of  sunlight is higher than incandescent light, which  has a low color temperature. That’s why sunlight looks whiter, bluish than indoor lighting which looks yellow/orangish. When you walked outside with the video camera, the camera was adjusted for the concept of what white is, indoors and the video colors comes out all wrong.  Some cameras can adjust the white balance on the fly, but it still takes time for the electronics to capture, analyze and adjust. The transition of indoor white balance to outdoor white balance by the camera may sometimes be seen as you continue to watch the video.

As you are probably already aware, color begins to disappear (be absorbed by the water) as you descend down the water column.  Without setting or telling the camera what white is underwater, the electronics can only use what it sees as the base often resulting in blue footage. Some techniques to compensate for this color loss; lights, filters and white balancing. Lights and filters will be covered under a different post.

If your camera and housing provide the option to manually adjust/set the white balance,  point your camera at a white object, (usually a slate) zoom in so the white fills the majority of the screen, and activate the white balance control.  Some cameras do not have the ability to set the white balance and will set it automatically.  If your video camera only has auto white balance, you can often set it by zooming in to a white object, turning the camera off, then turning it back on while still focused on the white object. The camera should read the white slate as white when it turns on.  Other cameras with auto white balance will adjust if you hold steady for a few seconds on the white card. When looking for a camera, I recommend looking for a camera/housing combination that allows for manual white balance control.

Things to consider:
1 – Generally, try to white balance every ten or so feet of change in depth if shooting within a range of depths vs. white balancing against the sand/slate at the bottom , where you may spend most of your dive.
2 – White balance with your filter in place. Experiment with this because conditions are diverse such as turbidity, amount of natural lighting, current and so forth.

3 – For cameras white balance needs to be set before securing the housing, try white balancing against a green screen. ie. from your PCs monitor. The video should appear redish. Adjust the green as needed. If you have a filter that can be attached/detached, try that in addition for comparision.

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