Photography Terms PDF

Lecture 1 Expressive an image created with the intention of reflecting inner thoughts. photography Intentions the photographer's thoughts about a photograph, including answers to the following questions: What do you want to photograph...

Lecture 1 Expressive an image created with the intention of reflecting inner thoughts. photography Intentions the photographer's thoughts about a photograph, including answers to the following questions: What do you want to photograph? Why do you want to photograph it? What message are you trying to send to your viewers? What action or reaction do you hope to elicit from your viewers?   Lecture 2 Angle of in regard to large-format lenses, the angle of coverage is the maximum image area of usable quality coverage captured by a given lens. Depending on their design, two lenses with the same focal length may have different angles of coverage. Angle of view the portion of the scene that the lens sees. The angle of view is sometimes called the image circle. Aperture the actual opening in a lens created by the diaphragm. Its size dictates the amount of light allowed through the lens as you make a photograph. Bits digital bits of information in binary code (0s and 1s). Charge-coupled a solid-state imager (sensor) that converts light coming through the lens into electronic signals. device (CCD) Because of high costs, most digital cameras have switched to a different solid-state sensor called CMOS. CMOS A sensor that collects light coming through the lens and converts it to electronic signals. Although a (complementary CMOS sensor may not be able to match the quality of the imaged created by CCDs, its smaller size metal-oxide and much lower cost make CMOS sensors the ideal choice for most consumer digital cameras. semiconductor) Correct meaning that the film negative (or digital information) produces a photograph in which the light areas exposure and light-colored objects are as light as expected and the shadows and dark objects are as dark as expected from the scene being photographed. Covering power a measurement of the size of the image a lens makes inside the camera. Different lenses of the same (coverage) focal length are manufactured to produce a variety of angles of coverage. Diaphragm an arrangement of flat, thin pieces of metal that overlap and work together inside the lens to create a variablesized opening for the light to pass through. f-stop (relative a measurement found by dividing the focal length of a lens by the effective diameter of its aperture. aperture) Fast lens a lens with unusually wide aperture capabilities. Aperture settings of 1.4 or 2.8 allow photographers to use faster shutter speeds because so much light can enter the lens. Film plane the place inside the camera where the film rests, ready to be exposed to light. Film must be exactly parallel to the lens to ensure that every portion is exposed and focused identically. Fixed focal length (prime) a lens designed with a single, or unchangeable, focal length. lens Focal length a measurement of the distance from the principal plane (outer edge) of the lens to the rear nodal point, the point at which light rays converge inside the lens to a single point; usually measured in millimeters. Focal-plane a multiple-component shutter mounted toward the back of the camera body, just forward of the film shutter plane, where the film travels. During an exposure, the shutter opens for a preset length of time, allowing for an exposure of varying speeds, depending on the shutter speed set for that photograph; synonymous with film-plane shutter. Frame an individual image recorded on the film or digital recording media. A ?frame? is one photograph. Full stop a specific incremental difference in light between one exposure setting and another. Changing the aperture or the shutter speed to exactly double or cut in half the amount of light for the exposure is changing that setting by 1 full stop. A 1-second shutter speed allows exactly 1 full stop more exposure of light than a half-second. Changing the aperture from f/5.6 to f/8, or f/16 to f/11, is a full-stop change. Gating the time during which a camera's sensor is collecting light information coming through the lens. Image circle a circular image projected onto the film or sensor as light passes through the lens. It always extends beyond the rectangle perimeter of the film or sensor, allowing the film or sensor to capture a rectangular (or square) image. Image a function that some cameras have, allowing them to steady themselves enough to compensate for stabilization natural camera shake, or movement from handholding a camera. (IS) Keystoning the deformity observed when a photograph is made with the camera on a different plane than the flat structure being photographed. The classic keystoning example is seen when a camera is tilted back to photograph a tall building. The top of the building appears much narrower than the bottom of the building. Leaf shutter a series of individual, spring-mounted metal leaves that move in an extremely fast, synchronous pattern to allow light into the camera, allowing almost all of the light from the scene to enter the camera at the same time. Light-tight meaning that light coming through the lens during an exposure is the only light that can reach the camera's film or sensor. Macro setting this lens feature allows a shorter minimum focusing distance than the same lens built without a macro setting. Some zoom lenses also come with macro settings. Minimum the least distance the camera can be set from the subject and have that subject come into focus. All focusing lenses have a minimum focusing distance. distance Negative as a photographic exposure is created, reflected light strikes the film surface. Once processed, the light sensitive film reacts by turning darker where the scene's light was brighter, and becomes increasingly transparent where the scene's light was darker. A photographic print is produced from a negative. Noise a phenomenon that occurs when CMOS sensors misread the electronic information, creating visual flecks that don't match the rest of an image. Normal focal the view from left to right within a scene approximately equal to the field of vision with only one eye length open. It can also be thought of as the approximate length of the diagonal of the camera's format. The diagonal length of a single frame of a 35 mm film (a single negative on a roll of 35 mm film) is approximately 50 mm. A normal lens is one that neither enlarges (draws objects in a scene closer) nor widens the view (pushes objects in a scene back). On 35 mm cameras, a 50 mm lens is considered normal. Optical coating a lens coating that increases the actual transmission of light to the camera. Optical coatings also reduce the amount of scattered light within the lens itself, therefore reducing the possibility of lens flare. Parallax a phenomenon causing a visual discrepancy between what is seen through the viewfinder and what the camera ultimately records, risking pictures that are slightly low and off center, even though the scene was perfectly composed when seen through the viewfinder. Pentaprism located above the mirror of an SLR camera, a pentaprism reverts the image to right-side up so you can see the scene as it appears when viewed in the real world. Photons tiny particles of light. Photosite one section of the grid of a light-sensitive section of a CMOS or CCD sensor. Also loosely referred to as a pixel, an acronym for picture elements. Each individual photosite creates 1 pixel of information in the final image. Pinhole camera a simple, light-tight box with a tiny hole on one side and a method of holding film on the opposite side. The earliest form of camera, the pinhole camera has no lens. Pixel an acronym for ?picture element.? A pixel is one tiny square within the photograph. It can represent any 1 of 16.7 million different colors, but it can only be one color at any given time. Point-and-shoot a term used for cameras with few controls. Either the camera determines exposure and focus settings automatically or there are limited adjustments designed into the device. Point-and-shoot cameras frequently have a rangefinder optical system. Positive another term for ?positive? would be ?as the scene looked.? Areas that were dark in the scene appear dark in the print; areas that were light in the scene appear light in the print. Prime lens a lens that has only one fixed focal length; to change how much to photograph within a scene, you need to move toward or away from that scene to make the change. Principal plane the plane including the point of the lens farthest distant from the camera body. Rangefinder the device that separates the viewfinder from the lens making the image. The viewfinder itself is optical system placed above and often to the side of the lens; therefore, the viewfinder doesn't point to the exact spot as the lens. Rear nodal the point at which the incoming light rays converge to a single point. The image traveling through the point lens flips upside down at the rear nodal point. Reflection loss the amount of light reflected back from the lens. Reflection loss, whenever light moves from air to glass, is typically about 7%. Modern antireflection optical coatings are capable of reducing the reflection loss to less than 0.5%. Scheimpflug a law of physics that describes the increased depth of field you get by tilting the front lens of a large- principle format camera forward while keeping the film plane in its original position. Shutter a mechanical barrier inside a camera that prevents light from contacting the film or sensor, except when the photographer opens and closes it when creating a photograph. Shutter speed the length of time the shutter remains open during a photographic exposure. Many advanced cameras are capable of shutter speeds ranging from 1/4,000 second to ?bulb,? which allows a photographer to lock a shutter open indefinitely, sometimes for hours. Slow lens a lens with unusually narrow maximum aperture capabilities. Maximum aperture settings of 5.6 or 8.0 force photographers to use unusually long shutter speeds to compensate for the decreased amount of light entering the lens. SLR camera a single-lens reflex camera uses an optical system involving a mirror and pentaprism inside the camera. The image seen in the viewfinder is the same as the image being taken in by the lens. There is no issue of parallax with SLR cameras. Telephoto lens a lens with a focal length longer than 50 mm in 35 mm cameras. Telephoto lenses act like binoculars in that they narrow the field of view and also magnify the scene. Telephoto view a field of view that is narrower than usual where objects in the frame appear closer to the photographer than they would with a normal lens. Viewfinder in a camera, a small window through which one looks to compose and focus the scene one is photographing. Viewfinder a camera design that uses a rangefinder optical system. Many point-and-shoot cameras use this system. camera Vignetting darkening of an image's corners by cutting off or shading the corners of a photograph. Vignetting can also be added in post-production in Photoshop. Wide-angle lens a lens with a focal length shorter than 50 mm in 35 mm cameras. Wide-angle lenses allow photography of large areas, such as mountains or football stadiums. Wide-angle a broader, wider field of view than a normal view. Typically, objects in the wide field of view appear view to be farther away from the photographer than they would with a normal lens. Zoom lens a lens with variable focal length capability. Typically, a zoom lens ranges from medium wide-angle to medium telephoto ability and can be infinitely varied between the two.       Lecture 3 18% (middle) the average between pure black and pure white. 18% gray is what the light meter renders all exposures gray unless the photographer overrides the light meter when making the exposure. Aperture the actual opening in a lens created by the diaphragm. Its size dictates the amount of light allowed through the lens as you make a photograph. Aperture a camera mode that allows you to select an aperture setting according to the depth of field you want for Priority (Av) your photo. mode Bit depth a reference to the number of colors that can be displayed within an image. The greater the bit depth, the more colors available to be used in an image. Black point the point at which pixels have a value of 0 in each of the Red, Green, and Blue channels in the RGB color system, or they have the value of 100% in each of the Cyan, Magenta, Yellow, and Black channels of the CMYK color system; also called pure darkness. Blocked-up an exposure that falls on the shoulder or toe of a characteristic curve. That part of the exposure will not shadows be able to render clear separation between the tones, resulting in dark areas with little or no detail. Blooming the point where light information hitting photosites starts to spill over to other photosites, producing a featureless white spot. A purple fringe is visible when those white areas within the photograph are adjacent to very dark areas. Blown-out the result of overexposure that causes a loss of detail in the lightest portion of a photograph. highlights Brightness a term loosely equivalent to light. In Photoshop, brightness is used in relation to the range of visible light ranging from pure black to pure white within a photograph. Bulb mode a camera mode that allows the camera's shutter to remain open as long as the shutter button is pushed. Center- the metering system of a camera takes the entire scene into account, but gives more attention to the weighted center of the frame (where photographers often compose a scene). The metering system gives more averaging ?weight? to the center of the frame when choosing a proper exposure. Closing (stopping) decreasing the diameter of the aperture or changing the f-stop to a smaller opening, such as from f/4 to down the f/5.6. aperture Density the build-up of silver in the exposed frames on the negative. The darker areas within a negative are  considered denser than the lighter areas. Depth of field how much of a scene is in focus from close to the camera to distant from the camera. Depth of field is a function of aperture; a wide-open aperture such as f/4 results in a shallow depth of field, and a narrow aperture such as f/22 will record a scene with a greater depth of field. DX code a magnetic code that tells the camera what the film's speed (ISO) is and automatically sets that ISO value in the camera's metering system. If your camera can't read the DX code, you must use a dial on your camera to manually select the proper film speed. Dynamic the breadth of the range of contrast between pure black and pure white that film or digital cameras can Range record. Film grain the empty space between the particles of silver on film. When negatives from higher ISO films are enlarged to prints, the empty space between the particles of silver on the film can make the prints appear grainy. Frame an individual image recorded on the film or digital recording media. A ?frame? is one photograph. Gray card a camera accessory manufactured to give 18% gray reflectance. Highlights bright areas in a scene or photograph that contain details that add to your understanding of the image. Incident light the available light that happens to be falling onto your object, regardless of the light source. ISO (orcASA) an agreed-upon standard of measurement of the sensitivity of film or digital sensor to light. Leakage when heat generated in the CCD or CMOS sensor creates an electrical signal indistinguishable from the current signal originating from light coming through the lens. Leakage current is sometimes called dark current. Manual (M) a camera mode that allows you to set both the aperture and shutter speed. mode Middle gray the halfway point between the brightest possible value (white) and the darkest possible value (black). Midtone a reflected light value that falls between the highlights and the shadows; an area of medium brightness in a scene or photograph. Noise a phenomenon that occurs when CMOS sensors misread the electronic information, creating visual flecks that don't match the rest of an image. Opening up the increasing the diameter of the aperture; changing the f-stop to a larger opening, such as from f/11 to f/8. aperture Overexposure allowing an exposure of more light than needed to reach the photographically sensitive material. Shadow (dark) areas will be lighter than expected, and lighter areas may be so light as to not record detail. Overexposure can be an intentional tool used by knowledgeable photographers who wish to impart aesthetic qualities. Posterization the shifting of colors within a photograph due to changes within Levels or Curves, resulting in many values that have no pixels on a histogram. Program mode a camera mode that typically reads the film's or camera's ISO setting and then invokes your camera's light meter to select the proper aperture and shutter speed for the exposure. Reflective light an in-camera meter that measures the amount of light reflected from the scene and sets the exposure meter accordingly. Shadows dark areas in a scene, slide (transparency), or print that may contain detail or may be too dark to hold any detail. Shutter a camera mode that allows you to select a shutter speed setting according to your need to stop action in Priority (Tv) your scene. mode Shutter speed the length of time the shutter remains open during a photographic exposure. Many advanced cameras are capable of shutter speeds ranging from 1/4,000 second to ?bulb,? which allows a photographer to lock a shutter open indefinitely, sometimes for hours. Silhouette an image in which the subject is so dark as to be nearly or totally void of detail, and the surrounding scene is lighter and almost always contains much more visual information. A silhouette is most often backlit. Specular very bright areas created by light bouncing off chrome, headlights, or other highly reflective surfaces highlights within the photograph. Sunny f/16 when photographing outdoors on a sunny day, use the following formula: 1/ISO = shutter speed at an Rule aperture of f/16. The Zone a system of evaluating reflected light and exposure values that Ansel Adams introduced to the System photographic world in his book, The Negative, in 1981. Underexposure an exposure of less light than needed to properly record a scene onto film or sensor. Shadow areas are darker than expected and may not contain intended detail. Lighter areas are darker than expected. Accomplished photographers can intentionally use underexposure to impart aesthetic qualities. Value the range of black through progressively lighter grays to white within an image; typically described as light, medium, or dark. White point the point at which pixels have a value of 255 in each Red, Green, and Blue channel in the RGB color system, or they have the value of 0% in each of the Cyan, Magenta, Yellow, and Black channel of the CMYK color system.