GLOSSARY G
Glossary
Active D-Lighting A camera setting that preserves highlight and shadow details in a high-contrast scene that has a wide dynamic range.
AE (Auto-Exposure) A function of a camera where the camera selects the aperture and/or shutter speed according to the camera's built-in light meter. See also Aperture Priority, Shutter Priority, and Programmed Auto.
AE/AF (Auto-Exposure/Autofocus) Lock A camera control you use to lock the current metered exposure and/or autofocus setting prior to taking a photo. This allows you to meter an off-center subject and then recompose the shot while retaining the proper exposure for the subject. The function of this button is selected in the Setup menu under the Buttons heading.
AF-assist illuminator An LED light that's emitted in low-light or low-contrast situations. The AF-assist illuminator provides enough light for the camera's AF to work in low light.
ambient lighting Lighting that naturally exists in a scene.
angle of view The area of a scene that a lens can capture, which is determined by the focal length of the lens. Lenses with a shorter focal length have a wider angle of view than lenses with a longer focal length.
aperture The opening of the lens similar to the iris of an eye. The designation for each step in the aperture is called the f-stop. The smaller the f-stop (or f-number), the larger the actual opening of the aperture; the higher-numbered f-stops designate smaller apertures, letting in less light. The f-number is the ratio of the focal length to the aperture diameter.
Aperture Priority An exposure mode setting where you choose the aperture and the camera automatically adjusts the shutter speed according to the camera's metered readings. Aperture Priority is often used by a photographer to control depth of field.
aspect ratio The ratio of the long edge of an image to the short edge as printed, displayed on a monitor, or captured by a digital camera.
autofocus The capability of a camera to determine the proper focus of the subject automatically.
backlighting A lighting effect produced when the main light source is located behind the subject. Backlighting can be used to create a silhouette effect or to illuminate translucent objects. See also frontlighting and sidelighting.
barrel distortion An aberration in a lens in which the lines at the edges and sides of the image are bowed outward. This distortion is usually found in shorter focal-length (wide-angle) lenses.
bounce flash Pointing the flash head in an upward position or toward a wall so that it bounces off another surface before reaching the subject, which softens the light reaching the subject. This often eliminates shadows and provides smoother light for portraits.
bracketing A photographic technique in which you vary the exposure over two or more frames. By doing this, you ensure a proper exposure in difficult lighting situations where your camera's meter can be fooled.
broad lighting The lighting when your main light illuminates the side of the subject who's facing you.
camera shake Camera movement, usually occurring at slower shutter speeds, which produces a blurred image.
catchlight Highlight that appears in the subject's eyes.
Center-weighted meter A light-measuring device that emphasizes the area in the middle of the frame when you're calculating the correct exposure for an image.
colored gel filters Colored translucent filters that are placed over a flash head or light to change the color of the light emitted on the subject. Colored gels can be used to create a colored hue of an image. Gels are often used to match the flash output with the ambient light as well as to change the color of a background when shooting portraits or still lifes; the gel is placed over the flash head and then the flash is fired toward the background.
compression Reducing the size of a file by digital encoding, which uses fewer bits of information to represent the original subject.
Continuous Autofocus (AF-C) A camera setting that allows the camera to continually focus on a moving subject.
contrast The range between the lightest and darkest tones in an image. In a high-contrast image, the tones fall at the extremes of the range between white and black. In a low-contrast image, the tones are closer together.
dedicated flash An electronic flash unit, such as the Nikon SB-900, SB-800, SB-700 SB-600, or SB-400, designed to work with the autoexposure features of a specific camera.
depth of field (DOF) The portion of a scene from foreground to background that appears sharp in the image.
diffuse lighting A soft, low-contrast lighting.
D-Lighting A function within the camera that can fix the underexposure that often happens to images that are backlit or in deep shadows. This is accomplished by adjusting the levels of the image after it's been captured. Not to be confused with Active D-Lighting.
DX Nikon's designation for digital single lens reflex cameras (dSLRs) that use an APS-C–sized (23.6mm × 15.8mm) sensor.
equivalent focal length A DX-format digital camera's focal length, which is translated into the corresponding values for 35mm film or the FX format.
exposure The amount of light allowed to reach the sensor, which is determined by the ISO setting, the amount admitted by the aperture of the lens, and the length of time determined by the shutter speed.
exposure compensation A technique for adjusting the exposure indicated by a photographic exposure meter when factors may cause the indicated exposure to result in a less-than-optimal image.
exposure mode Camera settings that control how the exposure settings are determined. The D7000 also offers scene modes, which are automatic modes that adjust the settings to predetermined parameters, such as a wide aperture for the Portrait mode. See also Aperture Priority, Shutter Priority, and Programmed Auto.
fill flash A lighting technique where the Speedlight provides enough light to illuminate the subject to eliminate shadows. Using a flash for outdoor portraits often brightens the subject in conditions where the camera meters light from a broader scene.
fill lighting The lighting used to illuminate shadows. Reflectors or additional incandescent lighting or electronic flash can be used to brighten shadows. One common outdoor technique is to use the camera's flash as a fill.
flash An external light source that produces an almost instant flash of light to illuminate a scene. Also known as electronic flash.
Flash Exposure Compensation (FEC) Adjusting the flash output. If images are too dark (underexposed), you can use FEC to increase the flash output. If images are too bright (overexposed), you can use FEC to reduce the flash output.
flash modes Modes that enable you to control the output of the flash by using different parameters. Some of these modes include Red-Eye Reduction and Slow Sync.
flash output level The output level of the flash as determined by one of the flash modes.
Front-curtain sync Front-curtain sync causes the flash to fire at the beginning of the exposure when the shutter is completely open in the instant that the first curtain of the focal plane shutter finishes its movement across the film or sensor plane. This is the default setting. See also Rear-curtain sync.
frontlighting The illumination coming from the direction of the camera. See also backlighting and sidelighting.
f-stop See aperture.
histogram A graphic representation of the range of tones in an image.
hot shoe The slot located on the top of the camera where the flash connects.
ISO sensitivity The ISO (International Organization for Standardization) setting on the camera indicates the light sensitivity. In digital cameras, lower ISO settings provide better quality images with less image noise; however, a lower ISO setting requires more exposure time.
JPEG (Joint Photographic Experts Group) This is an image format that compresses the image data from the camera to achieve a smaller file size. The compression algorithm discards some of the detail when closing the image. The degree of compression can be adjusted, allowing a selectable tradeoff between storage size and image quality. JPEG is the most common image format used by digital cameras and other photographic image-capture devices.
Kelvin A unit of measurement of color temperature based on a theoretical black body that glows a specific color when heated to a certain temperature. The sun is approximately 5500K.
lag time The length of time between when the Shutter Release button is pressed and the shutter is actually released; the lag time on the D7000 is so short, it's almost imperceptible. Compact digital cameras are notorious for having long lag times, which can cause you to miss important shots.
leading line An element in a composition that leads a viewer's eye toward the subject.
lens flare An effect caused by stray light reflecting off the many glass elements of a lens. Lens shades typically prevent lens glare, but sometimes you can choose to use it creatively by purposely introducing flare into your image.
lighting ratio The proportion between the amount of light falling on the subject from the main light and the secondary light, such as 2:1 — a ratio in which one light is twice as bright as the other.
macro lens A lens with the capability to focus at a very close range, enabling extreme close-up photographs.
manual exposure Bypassing the camera's internal light meter settings in favor of setting the shutter and aperture manually. Manual exposure is beneficial in difficult lighting situations where the camera's meter doesn't provide correct results. When you switch to manual settings, you may need to review a series of photos on the digital camera's LCD to determine the correct exposure.
Matrix metering The Matrix meter (Nikon exclusive) reads the brightness and contrast throughout the entire frame and matches those readings against a database of images (more than 30,000 in most Nikon cameras) to calculate the best exposure value.
metering Measuring the amount of light by using a light meter.
NEF (Nikon Electronic File) The name of Nikon's RAW file format.
noise Pixels with randomly distributed color values in a digital image. Noise in digital photographs tends to be more pronounced with low-light conditions and long exposures, particularly when you set your camera to a higher ISO setting.
noise reduction (NR) A technology used to decrease the amount of random information in a digital image, often caused by long exposures and/or high ISO settings.
pincushion distortion A lens aberration in which the lines at the edges and sides of the image are bowed inward. It is usually found in longer focal-length (telephoto) lenses.
Programmed Auto (P) A camera setting where shutter speed and aperture are set automatically.
RAW An image file format that contains the unprocessed camera data as it was captured. Using this format allows you to change image parameters, such as white balance saturation and sharpening. Although you can process RAW files in-camera, the preferred method requires special software, such as Adobe Camera Raw (available in Photoshop), Adobe Lightroom, or Nikon's Capture NX 2 or ViewNX 2. See also NEF.
Rear-curtain sync Rear-curtain sync causes the flash to fire at the end of the exposure an instant before the second, or rear, curtain of the focal plane shutter begins to close. With slow shutter speeds, this feature can create a blur effect from the ambient light, which appears as patterns that follow a moving subject and the subject sharply frozen at the end of the blur trail. This setting is usually used in conjunction with longer shutter speeds. See also Front-curtain sync.
red-eye An effect from flash photography that appears to make a person's eyes glow red or an animal's yellow or green, caused by light bouncing from the retina of the eye. It is most noticeable in dimly lit situations (when the irises are wide open) as well as when the electronic flash is close to the lens and, therefore, prone to reflect the light directly back.
Red-Eye Reduction A flash mode controlled by a camera setting that's used to prevent the subject's eyes from appearing red in color.
rights-managed A term used to describe images for sale that are only allowed to be used for specific applications laid out in a contract.
royalty-free These types of images are bought outright and can be used without restrictions.
self-timer A mechanism that delays the opening of the shutter for several seconds after the Shutter Release button has been pressed.
short lighting When your main light is illuminating the side of the subject that's facing away from you.
shutter A mechanism that allows light to pass to the sensor for a specified amount of time.
Shutter Priority In this camera mode, you set the desired shutter speed and the camera automatically sets the aperture for you. When you're shooting action shots, it freezes the subject's motion by using fast shutter speeds.
shutter speed The length of time the shutter is open to allow light to fall onto the imaging sensor. The shutter speed is measured in seconds or, more commonly, fractions of seconds.
sidelighting Lighting that comes directly from the left or the right of the subject. See also frontlighting and backlighting.
Slow Sync A flash mode that allows the camera's shutter to stay open for a longer time to allow the ambient light to be recorded. The background receives more exposure, which gives the image a more natural appearance.
Speedlight A Nikon-specific term for its accessory flashes.
spot meter A metering system in which the exposure is based on a small area of the image. On the D7000 the spot is linked to the AF point.
TTL (Through-the-Lens) A metering system where the light is measured directly through the lens.
vanishing point The point at which parallel lines converge and seem to disappear.
Vibration Reduction (VR) A function of the lens in which the lens elements are shifted by a mechanism in the lens to reduce the effects of camera shake.
white balance A setting used to compensate for the differences in color temperature from different light sources. For example, a typical tungsten light bulb is yellow-orange, so the camera adds blue to the image to ensure that the light looks like standard white light.