158 The Digital Filmmaking Handbook, 4E

However, as you open your aperture, you’ll be letting in more light, which means you’ll need to go to a faster shutter speed. A faster shutter speed might result in more stuttery motion, so you’ll need to carefully balance your depth-of-field and shutter-speed concerns. As you’ll see later, you can also use special neutral density filters to reduce the amount of light entering the camera, allowing you more shutter speed flexibility.

Camera Equipment Checklist

You should keep these items in your camera bag for easy access at all times:

nYour camera’s original owner’s manual

nLens tissue

nLens cleaning fluid

nBlower brush

nMeasuring tape

nRain cover, umbrella, or plastic garbage bags

nSun shade

nExtra lenses (if applicable)

nLens filters

nExtra batteries (charged)

nA/C adapter

nFlashlight

nStandard tool kit

nSlate (see Chapter 9, “Shooting and Directing”)

nWhite pencil (for temporarily marking settings on the lens)

nColored tape (for marking blocking, camera, and light placement)

nGaffer’s tape (for who-knows-what, but when you need it, you need it)

nSmall bungee cords

nSmall alligator clamps

nLarge black cloth (to hide camera from reflective surfaces)

White Balancing

As you saw in Chapter 6, “Lighting,” different types of lights shine at different temperatures, or colors. One of the amazing characteristics of your eyeballs is that they can adjust automatically to all of these different temperatures, and can even understand mixed lighting temperatures—sunlight shining through a window into a fluorescent-lit room, for example.

Film and video cameras are not as sophisticated. Film has to be specially formulated for different types of light to represent color accurately. This is why there is film for daylight and film for tungsten light.

Digital image sensors have the same trouble. Fortunately, though, a digital camera’s understanding of color is entirely dependent on how the data coming off the sensor is processed by the camera’s internal computer. Therefore, by telling the camera what kind of light you’re shooting in, you can make sure that the camera interprets color data correctly.

White balancing is the process of getting a camera to represent white accurately. Because white light contains all other colors, if a camera can accurately reproduce white, then it can accurately render every other color. Color Plate 15 shows an example of an image that was incorrectly white balanced.

Your camera probably has an automatic white-balance setting that tries to white balance correctly on the fly. Automatic white-balance mechanisms can work very well, but for best results, you should take control of the white-balance process yourself.

Be aware that because the auto-white-balance mechanism is constantly white balancing, a sudden change in the luminance or color content of your scene can cause the camera to re-white balance, resulting in a weird color shift. For example, a giant pink elephant entering the frame might be enough to throw off the white balance for the entire scene. If you think your scene might be susceptible to such problems—or if you notice them when shooting— then you’ll want to use a manual white balance as described next.

Most cameras offer white-balance presets for different types of light. Therefore, you’ll have an option to select preset white-balance settings for daylight, or tungsten, or fluorescent lights. These can often prove better than auto-white-balance settings, especially if you’re shooting in a mixed light situation.

White Balance in °K

3000°K — White Tungsten

3700°K — Yellow Tungsten

4000°K — Fluorescent

4500°K — Fluorescent

5600°K — Sunlight

6500°K — Cloudy

7500°K — Shade

For the absolute best results, though, you should use your camera’s manual white-balance control. Getting yourself in the habit of always manually white balancing will help you shoot better footage and is essential for mixed-light situations.

To manually white balance, first set your lights. Then place something white in-frame, like a piece of foamcore or the back of a white script page. Make sure the white object is illuminated by the dominant light source(s) in your scene. Frame the camera so that only white shows in the viewfinder and activate the camera’s manual white-balance control.

Remember that you’ll need to re-white balance every time you significantly change the lighting, especially if you switch from daylight to tungsten light, or vice versa. Also, note that some cameras lose their manual white-balance reading if they are switched off or even placed in standby mode. If your camera functions like this, then you must remember to manually white balance when you restart the camera.

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Alternative White Balancing

You can use the white-balancing feature on your camera to achieve different color effects. White balancing against a bluish surface will result in a warmer-looking image, while balancing against an orange-ish surface results in a cool-looking image. Since white balancing affects the scene’s overall color temperature, it is sometimes easier to adjust the white balance than it is to place colored lighting gels on all your light sources. However, you’ll be hard-pressed to get your footage back to a normal color if you decide later that that’s what you need. As such, it’s almost always better to shoot good, normal-looking footage and then add any color effects later in postproduction.

Lens Filters

If your camera has threads on the end of its lens (Figure 7.14), you can attach special filters that will help you control color and composition better, as well as create special effects. Filters are simply specially prepared pieces of glass housed in a screw-on attachment. Most filters are threaded so that you can screw filters onto other filters to stack up effects. Filters come in different sizes, so the selection of filters available for your lens size might vary. Many filters come in different “strengths” whose values are usually measured with a simple number scheme—the higher the number, the stronger the effect you’ll get from the filter.

Figure 7.14

A selection of diffusion filters from Schneider.

UV Filters

As mentioned earlier, you should get at least one UV filter to protect your lens. In addition, UV filters will stop ultraviolet light from coming into the lens and will help reduce haze. There are a number of variations of UV filters, including stronger haze filters and warm UV filters, which will add warmth to your image.

Polarizing Filters

Polarizers are used to deepen saturation and improve contrast. Shooting with a polarizer will greatly improve images of cloudy skies, and they are valuable for all landscape shooting.

Polarizers can also be used to eliminate reflections when shooting through glass or windows (see Figure 7.15) and to eliminate hot spots on a reflective surface created by a light source.

Lens Filters (continued)

Figure 7.15

The window reflections in the left image can be easily eliminated with a polarizing filter in the right image.

Neutral Density Filters

Neutral density (ND) filters reduce the amount of light entering the lens in single f-stop increments, without changing the quality or color of the light. Therefore, if you’re shooting in bright sunlight (which normally requires a small aperture), but you want to shoot with a very shallow depth of field (which requires a large aperture), you can use ND filters to cut out enough light to facilitate a smaller f-stop value. ND filters can also be used to slow shutter speeds from fast, stuttery speeds to something a little more natural looking.

Your camera might have a built-in electronic ND filter. Check your manual to see how many f-stops this feature provides (see Figure 7.16).

You can also get gradated ND filters that are designed to darken bright skies, which can easily overexpose.

Figure 7.16

Many cameras offer built-in ND filters.