Jun 21, 2010

HVX200 White Balance made Simple

First, a little background into what White Balance is:

The human eye doesn't compensate for changes in color temperature, your brain does. When you move from outdoors to indoors your iris adjusts for the amount of light but your brain tricks you into thinking colors are the same. You actually have to learn to "see" color, which was one of the first things had to learn when shooting 35mm film, was to un-train my brain. You can actually see how yellow/red tungsten light is vs how blue things look in bright overhead cloudless sun (skylight) once you stop allowing your brain to make those adjustments for you - what us old-school film guys called "BCB" (brain color-blindness).

If you wanted your camera to see color just as your eyes do then the simple thing to do is never use any other color space than 5600k - that's what your eyes are "balanced" for. That's why most print and slide films are "daylight" balanced for 5600k, and color correction comes in the form of filters - or Photoshop. But, that's obviously not practical since indoors things get ruddy and fluorescents get green.

There's really 2 ways you can set WB in the HVX200:

1) Most are using the traditional method of putting a WB card in front of the camera and using the AUTO WB set button and let the camera determine the proper setting. This can cause inconsistent results depending on exactly what kind of light is hitting the WB card. For example: if your target is getting bright sun but you incorrectly hold the card and the camera sees shade then the subject will go blue, and vice-a-versa.

The other con to use the AWB button is that it can over-compensate when you don't want it to, say for example during sunsets. In the Color Sample Clip I posted you'll notice the sunset colors were really vibrant, even before custom color settings were applied. If I had used the AWB button during those segments the colors would have been much flatter and muted.

2) The second method is much simpler and takes the sometimes problematic issues of capturing the proper light on the WB card. The HVX200 has 2 built-in presets for WB which covers 90% of what you might shoot: 3200K (tungsten) for most studio work (this doesn't apply if you're using the newer studio fluorescent type lights) and 5600k for all outdoor/bright sun work. So the simple method is thus:

A - Put the WB switch on the side to PRESET
B - Tap the AWB button on the front; this toggles between 3200k and 5600k in the camera. Once set you can fine-tune the WB manually:
C - Goto the SCENE FILE menu and use the COLOR TEMP setting which will shift between bluer (minus settings) and redder (plus settings).

Once you eyeball a perfect color response with manual temp settings (if need be), you're done. Never use ATW (auto tracking white) unless you're in an ENG or documentary situation where the WB is constantly changing and you want the camera in AUTO exposure mode.

Note: If you're in a primarily fluorescent or mixed lighting situation you can still use the simplified method and fine tune to compensate or, just use the AWB button and white card to compensate.

With regard to how I shoot, I always shoot location work with the 5600k preset and manually tweak to compensate for skylight or overcast conditions, especially with skin tone and studio is always at 3200k and so far I haven't needed to tweak temp for studio work except for a few times when the studio lights were actually burning off-color.

If you shoot with D-SLR's you can use this same simple technique for WB; either manually dial-in 5600k or, use the bright sun preset which is the same. Studio strobes and on-camera flashes are also balanced for either 5600 or 5500k.

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