Nikon D7000 manual Exif See exchangeable image file format Exif

Glossary 493

Exif See exchangeable image file format (Exif).

exposure The amount of light allowed to reach the film or sensor, determined by the intensity of the light, the amount admitted by the iris of the lens, the length of time determined by the shutter speed, and the sensitivity of the sensor or film to light.

exposure compensation Exposure compensation, which uses exposure value (EV) set- tings, is a way of adding or decreasing exposure without the need to reference f/stops or shutter speeds. For example, if you tell your camera to add +1EV, it will provide twice as much exposure, either by using a larger f/stop, slower shutter speed, or both. The D7000 offers both conventional exposure compensation and flash exposure compensation.

fill lighting In photography, lighting used to illuminate shadows. Reflectors or addi- tional incandescent lighting or electronic flash can be used to brighten shadows. One common technique outdoors is to use the camera’s flash as a fill in sunlit situations.

filter In photography, a device that fits over the lens, changing the light in some way. In image editing, a feature that changes the pixels in an image to produce blurring, sharpening, and other special effects. Photoshop includes several interesting filter effects, including Lens Blur and Photo Filters.

flash sync The timing mechanism that ensures that an internal or external electronic flash fires at the correct time during the exposure cycle. A digital SLR’s flash sync speed is the highest shutter speed that can be used with flash, ordinarily 1/250th of a second with the Nikon D7000. See also front-curtain sync and rear-curtain sync.

focal length The distance between the film and the optical center of the lens when the lens is focused on infinity, usually measured in millimeters.

focal plane A line, perpendicular to the optical axis, which passes through the focal point forming a plane of sharp focus when the lens is set at infinity. A focal plane indi- cator is etched into the Nikon D7000 on the top panel.

focus tracking The ability of the automatic focus feature of a camera to change focus as the distance between the subject and the camera changes. One type of focus track- ing is predictive, in which the mechanism anticipates the motion of the object being focused on, and adjusts the focus to suit.

format To erase a memory card and prepare it to accept files.

fringing A chromatic aberration that produces fringes of color around the edges of sub- jects, caused by a lens’s inability to focus the various wavelengths of light onto the same spot. Purple fringing is especially troublesome with backlit images.