Photo Glossary

Cable release

A flexible cable device for releasing the shutter. Particularly used for slow shutter speeds when touching the camera may cause camera vibration and blurring of the image.

Camera angles

Various positions of the camera with respect to the subject, each giving a different viewpoint or perspective.

Camera obscura

It is the origin of the modern camera. In its simplest form it consisted of a darkened room with a small hole in one wall. Light rays could pass through the hole to transmit on to a screen, and inverted image of the scene outside.

Capacitor

A device used for accumulating and holding a charge of electricity. Used in electronic flash and some forms of electronic shutters.

Card

Memory chip that can be used to store images and data.

Cast

An overall bias of the image towards one colour.

Catchlight

The reflection of a light in the subjects eyes in a portrait.

CCD

Charged Coupled Device. A mechanism that converts light into a proportional (analog) electrical current; the two main types of CCD are linear arrays, used in flatbed scanners and digital copiers, and area arrays, found in camcorders, digital cameras, and the like.

Che Gevara

Ernesto Guevara de la Serna (1928 –1967) was an Argentine-born Marxist, politician, and leader of Cuban and internationalist guerrillas. Guevara became an icon of socialist revolutionary movements worldwide.The photo of Che Guevara made by Alberto Korda in 1964 became one of the symbols of the modern culture.

Chromatic aberration

This problem is caused when the camera lens do not focus the different wavelengths of light onto the exact same focal plane. It usually happens around subjects with a wide contrast and around the edges of the image in wide-angle shots.

Cibachrome

Color printing process that produces color prints directly from color slides.

Circle of confusion

Disks of light on the image, formed by the lens from points of light in the subject. The smaller these disks are in the image the sharper it appears.

Circular polarizer

A photographic filter designed to eliminate reflections from glass and water, including water in foliage, to intensify the color of the sky and color saturation in general.

Clearing agent

A chemical that neutralizes hypo in film or paper, reducing wash time and helping to provide a more stable image.

Close-up

A picture of a subject that fills the frame, usually with the subject looking particularly close to the camera.

Close-up attachment lens

An attachment lens that fits on the front of a camera lens, allowing photography at closer distances than normal for that lens. Also refers to a "macro lens" - a camera lens that permits macro photography.

CMYK

A color model based on four process colors: Cyan, Magenta, Yellow, and Black. The colors are mixed to create a full-color image on a printer.

Coated lens

A lens that has a thin layer of transparent substance applied to its surface to reduce light reflection from the surface.

Cold colors

It is colors at the blue end of the spectrum that suggest a cool atmosphere.

Collage

It is a composition employing various different materials combined with original artwork attached to some type of backing.

Color balance

It is a adjustment in color photographic processes ensuring that a neutral scale of gray tones is reproduced accurately.

Color compensatory filters

It is a pale colored filters used to warm or cool subject colors.

Color model

A system of classifying individual colors. CMYK is the color model used in printing. RGB is the color model used in TV sets and computer monitors. HSL, HSB, HSV, and LCH are color models that describe how we perceive color.

Color saturation

It is a purity or strength of color, due to the absence of black, white or gray.

Color temperature

The light spectrum is scientifically described in this term, and is measured in degrees Kelvin (° K). Average noon daylight has a color temperature of 5500K. A common tungsten house light bulb has a color temperature of 2800K. Tungsten studio lamps 3200K and photo lamps or photofloods 3400K.

Color temperature meter

It is a device for measuring the color temperature of a light source.

Color wheel

The circular relationship of all colors based on the frequencies of light at each color.

Coma

It is lens aberration producing asymmetrical distortion of points in the image.

Compact camera

A camera designed to allow easy portability or concealment.

Composition

The arrangement of the elements in a photograph.

Compound lens

It is a lens system consisting of two or more elements.

Compression

A digital process that reduces the number of bits in an image to reduce the file size. The benefit is that it takes less storage space and can be e-mailed quicker.

Condenser

A lens in the enlarger head or spotlight that concentrates the light to a point of focus.

Contrast

A measure of the rate of change of brightness in an image.

Contrast control filter

Filters used in black and white photography to emphasize contrast in various degrees. Contrast filters improve the separation of tones. The deeper colored the filter the more pronounced the contrast effect.

Contrast values

It is perceived difference between the light areas and the dark areas of a scene. The range of contrast levels between the highlights and the shadows is called contrast values.

Contrasty

It is great differences between the highlights and shadows.

Convertible lens

A multi-piece lens. The pieces assemble or disassemble to form different focal lengths.

Crop

It is removing unwanted areas to improve composition.

Cropping

To trim off edges of an image, removing unwanted areas to improve composition.

Curvature of field

It is lens aberration causing a curved plane of focus.

Cyanotype

It is a contact printing process producing a blue image on a white background.