Nikon D7000 manual Center-Weighted Metering

Chapter 4 ■ Getting the Right Exposure 107

■Color Matrix metering. If you’re using a non-CPU lens (such as an older manual focus lens) and have specified the focal length and maximum aperture in the Setup menu (as described in Chapter 10), then the D7000 uses plain old color Matrix metering, which evaluates exposure based only on brightness and color informa- tion detected in the scene.

■With other lenses. If you don’t specify focal length or maximum aperture for a non-CPU lens, the D7000 defaults to Center-weighted metering.

Matrix metering is best for most general subjects, because it is able to intelligently ana- lyze a scene and make an excellent guess of what kind of subject you’re shooting a great deal of the time. The camera can tell the difference between low-contrast and high-con- trast subjects by looking at the range of differences in brightness across the scene. Because the D7000 has a fairly good idea about what kind of subject matter you are shooting, it can underexpose slightly when appropriate to preserve highlight detail when image contrast is high. (It’s often possible to pull detail out of shadows that are too dark using an image editor, but once highlights are converted to white pixels, they are gone forever.)

CAUTION

If you’re using a strong filter, including a polarizing filter, split-color filter, or neutral-den- sity filter (particularly a graduated neutral-density filter), you should switch from Matrix metering to Center-weighted, because the filter can affect the relationships between the different areas of the frame used to calculate a Matrix exposure. For example, a polarizing filter produces a sky that is darker than usual, hindering the Matrix algorithm’s recogni- tion of a landscape photo. Extra dark or colored filters disturb the color relationships used for color Matrix metering, too.

Center-Weighted Metering

In this mode, the exposure meter emphasizes a zone in the center of the frame to cal- culate exposure, as shown in Figure 4.9. About 75 percent of the exposure is based on that central area, and the remaining exposure is based on the rest of the frame. The the- ory, here, is that, for most pictures, the main subject will be located in the center. So, if the D7000 reads the center portion and determines that the exposure for that region should be f/8 at 1/250th second, while the outer area, which is a bit darker, calls for f/4 at 1/125th second, the camera will give the center portion the most weight and arrive at a final exposure of f/5.6 at 1/250th second.

Center-weighting works best for portraits, architectural photos, backlit subjects with extra-bright backgrounds (such as snow or sand), and other pictures in which the most important subject is located in the middle of the frame, as in Figure 4.10. As the name