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Basic Lighting

| How the Camera Works | LCD and Viewfinder | White Balance |

| Light and Exposure | Using a Gray Card |

| Manual Exposure Control | Manual Focus Control |

Using A Gray Card

Professional videographers, cinematographers and still photographers realize that ten to eighteen percent is often only approximately correct. It's close enough to so many things, that most of us won't notice that the exposure is off, unless we look at the same scene shot by someone who knows how to control the light and set the exposure accurately. You may not have control over the light, but you can set the exposure correctly if you use an eighteen percent gray card, which you can buy at most photography shops.

As stated earlier, the problem with automatic exposure is that it gets it wrong if the objects in your scene don't add up to approximately eighteen percent reflectance. Carrying a gray card solves that problem by providing you with an object that's an exact mid-tone. When you use a gray card to set your exposure in place of the scene that may or may not be at eighteen percent reflectance, you get a consistently correct exposure setting regardless of the actual tones in your shot. As an added bonus, if the LCD or viewfinder is calibrated badly, you'll still get the correct exposure.

The procedure is similar to setting the white balance. Hold the gray card in front of or next to your subject, so that the card is lit just as your subject will be. Zoom in on the gray card so that it fills the frame. Lock the exposure by switching to manual, zoom out and set up your shot. Repeat the above whenever your lighting angle changes. This method should work for most consumer-grade video cameras with manual control. Higher-end cameras may have an exposure lock system that works a little differently. Your manual will tell you how yours works. Once you've figured out how to operate the manual control on your unit, you'll be able to use a gray card.

Of course, pulling out a gray card when your shooting on the go is not always practical. If using a gray card means you might miss an important shot or be unable to follow the action, chances are you'll choose to trust the automatic exposure or your own eye. Whether you decide to use a gray card or trust your eye, you'll need to learn how to operate your camera in manual exposure mode.

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