Photographic Glossary-B


B (Bulb) Setting
A shutter-speed setting on an adjustable camera that allows for time exposures. When set on B, the shutter will stay open as long as the shutter release button remains depressed. Another similar option is the "T" setting, where it never drains the battery power on automatic camera body.

B (bulb)
Is the letter on the shutter dial that the shutter will stay open while the real is depressed. This is used for time exposure that are longer than your camera's preset shutter speed.

Abbreviation that stands for " black and white. "

Back focus
Distance between the back surface of the lens and the image plane, when the lens is focused at infinity.

Background colour
This is the colour that appears when part of an image is erased, cut or deleted

Background Processing
Allows assignment of specific operations to the background while the computer continues to perform previously assigned instructions.

Areas shown behind the main subject in a picture. The part of the scene the appears behind the principal subject of the picture. The sharpness of the background can be influenced by apertures and shuttle set. In the flash mode, bulb setting usually is set for absorbing more ambience light (background information), so the end result of the exposure won't be pitch dark.

The dark coating, normally on the back of a film, but sometimes between emulsion and the base, to reduce halation. The backing dye disappears during the processing.

Backlight control
An exposure compensation introduced when the subject of a picture is lit from behind ( which can fool a camera's metering system, creating a silhouette effect ).

Light coming from behind the subject, toward the camera lens, so that the subject stands out vividly against the background. Sometimes produces a silhouette effect. Always use something (a hand, a lens shade to avoid the light falls onto the lens - to avoid lens flares). Light coming from behind the subject.

Information printed on the back of a picture by the photofinisher. The system standard requires the printing of frame number, film cassette number and processing date automatically on the back of each Advanced Photo System print; may also include more detailed information, such as customized titles and time and date of picture-taking.

A type of shield that prohibits light from entering an optical system.

Placement of colors, light and dark masses, or large and small objects in a picture to create harmony and equilibrium. Description applied to colour films to indicate their ability to produce acceptable colour response in various types of lighting. The films normally available are balanced for daylight (550~6000K photo lamps (3400K) or studio lamps (3200K).

Balanced fill-flash operation
A flash photography technique that balances flash illumination with the scene's ambient light. This automatic operation utilizes the some camera's Automatic Balanced Fill Flash System with TTL Multi Sensor and a compatible dedicated TTL Speedlight.A type of TTL auto flash operation which uses the camera's exposure meter to control ambient light exposure settings, integrated with flash exposure control. That is, flash output level is automatically compensated to balance with ambient light, resulting in a better exposure for both subject and background. Balanced fill-flash is required. In balanced fill-flash operation, flash output is controlled to keep it in balance with the ambient light on the scene. Nikon offers Automatic balanced Fill-Flash where flash output is automatically compensated to be in balance with the ambient light.

Ball Head
With out a ball head on a tripod or monopod, the camera must be mounted directly to the top of the 'pod and can only shoot in one position. The addition of a ball head allows the camera to be positioned in almost any direction with the aid of only one tightening nut. The disadvantage of a ball head is that it is much harder to control fine positioning as all directions at once must be controlled.

A visible stepping of shades in a gradient. A artifact of colour gradation in computer imaging, when graduated colours break into larger blocks of a single colour, reducing the smooth look of a proper gradation.

General term for the amount of data that can pass through a given channel at one time. When using a dialup connection, the Internet for example, your bandwidth is limited by your telephone connection and modem, and will typically be 2-4 kilobytes per second. Information requiring more than this flow of data will be impractical for this connection.

Barn door
Are an accessory used on spotlights and flood lamps to control the direction of light and width of the beam. Studio lighting is often modified to prevent light from reaching parts of the scene. In order to do this, something must be position to shadow that region. Barn doors have 4 to 6 doors which can be opened and closed to allow/disallow light to reach a particular region. Often they are used to direct light towards the backdrop, or the opposite, to prevent light from falling on the backdrop.

Barrel distortion
A lens aberration or defect that causes straight lines to bow outward away from the center of the image. Straight lines are bowed in at the edges of the picture frame resembling the sides of a barrel; present in small amounts in some wideangle or wideangle-zoom lenses, but uncorrected in fisheye lenses.

The chassis of a lens. It usually is cylindrical and contains the lens element and iris diaphragm.

Base exposure time
Is the initial exposure time used for making a "straight" print.

Base plus fog
The optical density of an unexposed area of processed film. This takes into consideration the density of both the base and the emulsion.

Base resolution
The PhotoCD image resolution (512 x 1024) that is established for display on current televisions.

The material on which the emulsion is coated on film, photographic paper or videotape. Available in a choice of materials, including paper, cellulose, triacetate, glass and estar.

In digital photography, this refers to an effect produced with a Photoshop filter, which makes an image appear to be slightly raised off the surface.

Batch numbers
Set of numbers printed on packages of sensitive materials to indicate common production coating.

Batch processing
The performing of a group of computer tasks at the same time.

Batch scanning
Sequential scanning of multiple originals using previously-defined, unique settings for each.

Batteries for digital cameras can range from AA size to NiCad (nickel-cadmium), to NiMH (nickel-metal hydride) to lithium ion.
nickel cadmium (NiCad): Rechargeable batteries that use an alkaline electrolyte. They have a longer life than non-rechargeable batteries. NiCad batteries have a memory, so they need to be run all the way down before recharging. Otherwise, they will begin to run out of power sooner.
nickel metal hydride (NiMH): A rechargeable battery that lasts longer than a NiCad and has no memory, so it is easier to manage.
lithium ion: More expensive than either the NiCad or NiMH, but holds a charge much longer.

Named after the French telecommunications technician Baudot. It is the unit used to measure data transfer (1 Baud = 1 bit/sec.). Therefore, for example, the specification - "28,800 Bauds" means that data can be transferred at a rate of 28,800 bits per second.

Bayer pattern
A pattern of red, green, and blue filters on the image sensor's photosites. There are twice as many green filters as the other colours because the human eye is more sensitive to green and therefore green colour accuracy is more important.

Bayonet lens mount
A method of mounting a lens onto a camera body. The lens is inserted into the camera and given a short turn to lock it into place. Except for a few instances, a bayonet mount camera will not accept bayonet mount lenses made by a different manufacturer. The most common method of lens mounting.

Bellows factor
The exposure compensation necessary when focusing on close subjects, which becomes necessary when the subject is closer than ten times the focal length of the lens. As a lens is placed closer to the subject, focusing the lens causes it to move farther from the film, and, therefore, less light falls on the film. Consequently the exposure must be increased.

A flexible piece of material that is placed between the lens and the camera body, usually mounted on rails. The rails allow the bellows to be adjusted to change the distance between the lens and the body. This can be used to enable macro photography and close focusing. The flexible bellows also allow larger format cameras to tilt the lens with respect to the film plane to alter the perspective. An accordion-like, light tight device. On a camera, it goes between the lens and the camera body. When used as an accessory to a 35mm camera, it enables it to focus on a close subject and achieve a greater-than life-size magnification on film. On an enlarger, it goes between the lens and the enlarger head and the lens is focused by adjusting the length of the bellows.

Between-The-Lens Shutter
A shutter whose blades operate between two elements of the lens. Most medium format cameras like the Hasselblad have one family of lens with shuttle and another without. Most lenses in this family have a smaller maximum aperture than the other family.

Bézier curve
A mathematical curve that describes a vector path. In Photoshop Bézier curves are created by plotting anchor points with the pen tool.

Bi-concave lens
A simple lens or lens shape within a compound lens, whose surfaces curve toward the optical center. Such a lens causes light rays to diverge.

Big data
Any part of a layer that extends outside the physical dimensions of a Photoshop document.

A type of image containing only black and white pixels.

Binary number system
A numbering system used in computers consisting of only 1's and 0's.

Basic input / output system. The computer part that manages communications between the computer and peripherals.

Bit depth
This refers to the grey scale range of an individual pixel. A pixel with 8 bits per colour gives a 24 bit image (8 bits X 3 colours is 24 bits). CCD sensors are coloured in a pixel by pixel method. 30/32 bit colour is billions of colours
24 bit colour resolution is 16.7 million colours.
16 bit colour is 65,536 colours
8 bit colour is 256 colours
8 bit grey scale is 256 shades of grey
1 bit is black or white.

Bit mapped image
An image created from a series of bits and bytes that form pixels. Each pixel can vary in colour or gray-scale value. Also known as a raster image.

The basic unit in a binary numbering system. Binary Digit.
A single bit is expressed in the base 2, either on or off. Imagine using bits of data to express gray scale. Progressive levels display are expressed as increasing powers of 2. In a one bit system (21) there would only be white or black. A four bit system is 24 (16 gray scale levels) where a six bit system is 26 (64 levels of gray). The more gray, the better the picture.

The method of storing information that maps an image pixel, bit by bit. There are many bitmapped file formats, .bmp, .pcx, .pict, .pict-2, tiff, .tiff, .gif (89a), and so on. Most image files are bit mapped. This type of file gives you the jaggies, when examined closely you can see the line of pixels that create edges. Bitmap images are used by all computers. The desktop or screen information for all Windows machines uses .bmp files, while the Macintosh uses pict files

An image or file comprised of pixel or dot values of either black or white.

Black generation
When converting an RGB image to CMYK colour mode, black generation refers to the values that are generated for the black plate used in commercial printing.

Black limit
A colour separation setting that establishes the maximum percentage of black ink in a CMYK image. The setting is made before an RGB image is converted to a CMYK image. The press and paper planned for the publication usually determine the proper black limit setting.

Black point compensation
A setting in Photoshop that adjusts for differences in black points when converting colours. When selected, the full dynamic range of the source colour space is mapped to the full dynamic range of the destination colour space. When deselected, the dynamic range of the source colour space is simulated in the destination colour space.

Black point
This is the colour that produces colour values of 0, 0, 0 for each of the RGB components when scanned or digitized. Normally, the black point is 0 percent neutral reflectance or transmittance.

In four-colour printing (CMYK) black is the fourth colour, represented by the " K ".

A chemical bath to convert the black metallic silver that forms a photographic image into a compound such as a silver halide, which can then be dissolved or dyed. Bleach is used in toning and in many colour processes.

Printing term referring to an image or inked area which extends to the edge of a printed piece. The bleed is the portion of the artwork that is beyond the trim marks of the piece. The bleed is required to account for any slight misalignment during trimming which would otherwise result in an unprinted strip of paper appearing at the edge of the finished piece.

Pimples, scars, spots, and other defects which may be softened or removed by negative retouching, print spotting, and/or airbrushing (sometimes called "artifacts").

In computer graphics software, the intermediate steps between two objects that are created when the objects are merged together via a specified number of intermediate transformations.

Each pixel (photosite) on a digital camera sensor (CCD/CMOS) has a limit as to how much charge it can store. Blooming (or Streaking) is the name given to an overflow of charge from an over saturated pixel (photosite) to the next on the sensor. This problem is addressed with the addition of "anti-blooming gates" which can be thought of as vertical drain ditches running beside each row of pixels, these gates allow the overflowing charge to run away without affecting surrounding pixels. Anti-blooming gates, while mostly successful (and certainly for more modern sensors) blooming can still be a problem in very extreme exposures (very bright edge against a virtually black edge) and is typically visible as either a vertical streak or white halo extending for several pixels. The effects of blooming often amplify the visibility of chromatic aberrations. Blooming is really good at destroying the detail of leaves shot against a bright sky.

Sheets of absorbent paper made expressly for photographic use. Wet prints dry when placed between blotters.

An enlargement; a print that is made larger than the negative or slide. Slang for an enlargement, a print that is made larger than the negative or slide.

The art of softening the detail of a image. The process can be applied selectively to portions of an image.

File format extension for bitmap images.

The light-tight box that contains the camera mechanisms and protects the film from light until you are ready to make an exposure.

A adjustable metal arm, attached to a firm stand, on which lighting can be mounted. Some booms are also made to support camera.

To start or restart your computer; loading your operating system.

Automatically locating the correct edge of an image on a scan so that marking from the edge, frame, etc is not capture.

Bottom weighted
Refers to the area of the picture that the camera will meter for exposure. When making an auto exposure the camera is programmed to look at a number of spots in the scene, and if the camera was designed to use bottom weighted metering, most of those spots will be in the lower half of the picture. (See center weighted and exposure.)

Bounce flash
Flash illuminating a subject by reflection off a surface as opposed to direct flash, which is flash light aimed straight at the subject. Sometimes also called  " Bounce lighting." 

Bounce light
Light that does not travel directly from its source (bounce flash) to the subject but is first reflected off another surface. This technique softens the light by directing it at a ceiling, wall, board, or similar surface before it reaches the subject. Flash or tungsten light bounced off a reflector (such as the ceiling or walls) or attachment that fits on the flash (like the LumiQuest's Pocket Bouncer) to give the effect of natural or available light.

Box camera
Simple camera with a fixed, single-element lens and a light-tight box to hold the film. The shutter and aperture are usually pre-determined and unalterable (typically 1/25 sec at ƒ11.) Early consumer cameras developed by George Eastman were box cameras (e.g. the “Brownie” camera) . They could not be focused, per se. The lens was set to a hyperfocal distance that gave acceptably-sharp pictures if the subject was a given distance from the camera and correct exposure depended upon bright sun illuminating the scene.

Bpi (Bits per Inch)
Defines the density of data in a bitmap image.

Bps( bits per second )
Refers to the number of bits transferred in one second. The bps not often found on modems and serial interfaces.

Bracket flash
Often called handle mount flash. It comprised of one arm of the L-shaped bracket extends under the camera body and uses the camera's tripod socket to mount the camera on the bracket. The vertical arm of the bracket serves as a handle and mounts a flash unit in an accessory shoe often on top of the handle portion, but there are other methods. Flash mounted in a bracket usually requires a separate electrical cord to make the electrical connection between camera body and flash unit.

Camera meters cannot always meter a scene correctly because they must meter over a great deal of the frame. If you are unsure of the camera settings and want to make sure one of the shots is acceptable the best way to ensure that the shot comes out is to bracket. Bracketing involves shooting one exposure at the metered value, then shoot the next exposure at one or two stops below the metered value and also above the metered value. By using this technique more film is used, but there is a greater chance that a shot will come out properly exposed. Taking a series of photographs of the same subject at different exposures to insure the "correct" exposure; useful when shooting in situations where a normal metering reading is difficult to obtain. Taking additional pictures of the subject through a range of exposures-both lighter and darker-when unsure of the correct exposure. Some top cameras have provision for automatic bracketing, while manually you can bracket by the use of, say, adjust apertures or shuttle speeds setting or both, manually influent the ASA setting or even adjust the flash output power etc.To make several exposures, some greater and some less than the exposure that is calculated to be corrected. Bracketing allows for error and permits selection of the best exposure after development.

Brightness range
The difference in luminance between the darkest and lightest areas of the subject, in both negative and print.

The balance of light and dark shades in a image. Brightness is distinct from contrast, which measures the range between the darkness and lightest shades in a image. Brightness determines the intensity of shades; contrast determines the number of shades you get.

The intensity of light reflected from a surface. It is sometimes an alternative term for luminosity.

Broad Lighting
Conventional portraiture often positions the model in a pose such that their bodies are not facing the camera directly, but are turned to one side or the other. If the main light is positioned such that the illuminated portion of the face is framed in the image rather than the shadowed portion as in Short Lighting.

A highly involved process than can generate one print or, in a transfer variation, many copies. Its chief quality is a delicate painted/etched look. Lithographic ink is applied with a special brush to a gelatinized paper surface that selectively resists or attracts the ink.

A program used to display information, especially on the Internet.

Buffer ram
Fast memory chip in a digital camera. Buffer Ram is used to store images whilst they are recorded onto the much slower removable media card. This allows cameras to take a number of shots in rapid succession without waiting for the previous image(s) to be written to the card.

A special area set aside either in hardware or software for temporary storage. Usually, the bigger the buffer, the faster the computer can process other data.

Built-in light meter
A reflective exposure meter that is a built-in component of a camera so that exposures can be easily made for the cameras position.

Flashbulbs - A special flashbulb that can be used at certain shutter speeds is called "FP" where the initials stand for Focal Plane. Designed for use with focal-plane shutters these bulbs make a nearly uniform amount of light for a relatively long time. The idea is to turn on the light before the focal-plane shutter starts to open and keep the light on until the shutter is completely closed. Firing delay for flashbulbs is indicated by code letters: "F"- fast; "M"- medium; "MF" - medium fast; "S" - slow

Bulb setting
A shutter setting marked B at which the shutter remains open as long as the shutter release is held down. This is used for time exposures that are longer than your camera's preset shutter speeds. Most cameras have a slowest exposure setting of 1 seconds, some modern electronic cameras can stay open for 30 seconds. Sometimes that is not long enough for time laps photography. The B setting on the dial stands for bulb. In bulb mode the camera stays open as long as the shutter release is held down. This is useful when taking photos at night lightning, comets and other astronomical events, and many other uses. The bulb setting also allows you to darken a room, open the shutter, then set off flashes as necessary to properly expose a frame or show a stroboscopic effect. One thing to keep in mind is that on long exposures is that even slight movements will be noticed, especially if the subject is bright compared to the rest of the scent. The bulb setting should ONLY be used on a tripod. Two methods for limiting camera shake are the Mirror Lock Up feature, or MLU, and the Cable Release.

Bulk film
Film produced in very long, uncut strips - rolls that are too long to fit into cameras not equipped with a bulk camera back accessory. Many photographers buy their film in bulk, then load the bulk film into a “bulk film loader” which permits them to cut the bulk film into however many frames they wish, and to load the smaller strips into film cartridges that permit film reloading. It is an economical way to purchase film.

Basically, a darkroom process that gives additional exposure to part of the image projected on an enlarger easel to make that area of the print darker. This is accomplished after the basic exposure by extending the exposure time to allow additional image-forming light to strike the areas in the print you want to darken while holding back the image-forming light from the rest of the image. Sometimes called printing-in.

Burst images
A series of images taken in rapid succession, captured at a preset speed. Burst images are usually used to capture a person or object in motion. The number of images captured will vary, depending on how long the shutter button is held down and how much memory is available.

A path in the computer to transfer information within the computer or to the device(s) to which the data are addressed.

A unit of measure equal to 8 bits of digital information. The standard measurement unit of a file size. See also Kilobytes, Megabyte and Gigabyte.
1000 Bytes of computer information               =     1 Kilobyte
Kilobytes represents a million characters of information. 
1,000,000 Bytes of computer information       =     1 megabyte
Megabytes represents a million characters of information.
Actually one megabyte  =  1,048,576 bytes.
100,000,000 Bytes of computer information   =      1 Gigabyte
Gigabytes represents a 100 million characters of information.