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"C"-Format

CRC (Close Range Correction System): Check Nikon's terms page for more.

"Classic" format - one of the three selectable Advanced Photo System print formats; identical to the 2:3 aspect ratio used in 35 mm photography and suitable for most general-purpose shots.

Camera Angles

Various positions of the camera (high, medium, or low; and left, right, or straight on) with respect to the subject, each giving a different viewpoint, perspective or visual effect.

Camera shake.

Movement of camera caused by unsteady hold or support, vibration, etc., leading, particularly at slower shutter speeds, to a blurred image on the film. It is a major cause of un-sharp pictures, especially with long focus lenses.

Candid Pictures

Unposed pictures of people, often taken without the subject's knowledge. These usually appear more natural and relaxed than posed pictures.

Capacitor.

Electrical component once more commonly known as a condenser. Stores electrical energy supplied by a power source and can discharge it more rapidly than the source itself. Used in flash equipment, providing reliable bulb firing even from weak batteries, and supplying the surge needed for electronic flash tubes.

Cartridge

A lighttight, factory-loaded film container that can be placed in and removed from the camera in daylight. Some nature of film, like the infra red film, MUST not even try to load or unload film in any possible light existence, absolutely must be in total pitch dark condition to avoid fogging on film.

Cassette

Light-trapped film container used with 35 mm cameras.
Elliptically shaped film cassette designed especially for the Advanced Photo System that serves as the sealed, leaderless container for all System film whether unexposed, exposed or processed.

Cast.

Abnormal colouring of an image produced by departure from recommended exposure or processing conditions with a transparency film, or when making a colour print. Can also be caused by reflection within the subject as from a hat on to the face.

CCD

Electronic sensor used by all autofocus cameras, capable of detecting subject contrast; also an image-receiving device for video camera.

Cds

Cadmium Sulfide (Cell). A battery powered, current-modulating. light-sensing cell that was quite popular with lots of cameras exposure metering system and external metering devices. May be this extra will help, photo conductive material used in exposure meters as alternative to selenium-based or silicon blue photocells. Its electrical resistance decreases as the light falling on it increases. Cds meters use current from an external power source, such as a battery.

Chromatic aberration

A lens aberration producing an overall blurred image; the inability of a lens to bring all wavelengths of light (especially red and blue) into the same plane of focus; usually present in regular large-aperture telephoto and super-telephoto lenses; does not improve by stopping down the lens; correctable through the use of Iow Dispersion (ED, LD SD) glass. Basically, this aberration is caused by light rays of different wavelengths coming to focus at different distances from the lense. Blue will focus at the shortest distance and red at the greatest distance. Since the natural rays of light are a mixture of colors, each aberration will give a different value corresponding to each color thus producing blurred images.

CI

Contrast Index (sounds like composite index for stock market, ha!) Numeric rating indicating the optimum development contrast for negative materials.

Clearing Agent

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

Click stop.

Ball bearing and recess or similar construction used to enable shutter speeds, aperture values, etc. to be set by touch.

Close-Up

A picture taken with the subject close to the camera-usually less than two or three feet away, but it can be as close as a few inches.

Close-Up Lens

A lens attachment placed in front of a camera lens to permit taking pictures at a closer distance than the camera lens alone will allow.

Correction of Aberrations at Close Distance Focusing (or CRC)

In general, lenses are designed for maximum performance at infinity. Accordingly, when the lense barrel is fully extended to the shortest focusing distance, resolution is reduced. Although this is negligible for ordinary lenses, it becomes increasingly important in lense specially designed for close distance photography. Lense designers adopted a system where mechanism moves certain lense components as a unit automatically correcting for aberrations. This assures high lense performance throughout the focusing range.

Coated Lens

A lens covered with a very thin layer of transparent material that reduces the amount of light reflected by the surface of the lens. A coated lens is faster (transmits more light) than an uncoated lens.

Color Balance

How a color film reproduces the colors of a scene. Color films are made to be exposed by light of a certain color quality such as daylight or tungsten. Color balance also refers to the reproduction of colors in color prints, which can be altered during the printing process.

Colour negative.

Film designed to produce colour image with both tones and colours reversed for subsequent printing to a positive image, usually on paper.

Colour reversal.

Film designed to produce a normal colour positive image on the film exposed in the camera for subsequent viewing by transmitted light or projection on to a screen.

Colour temperature.

Description of the colour of a light-source by comparing it with the colour of light emitted by a (theoretical) perfect radiator at a particular temperature expressed in kelvins (K). Thus "photographic daylight" has a colour temperature of about 5500K. Photographic tungsten lights have colour temperatures of either 3400K or 3200K depending on their construction.

CompactFlash

Most digital cameras with PC Card interfaces use a storage technology called CompactFlash. Standard supported by the CompactFlash Association. CompactFlash is ATA compatible and will fit into any Type II or Type III slot when used with a passive adapter.

Component.

Part of a compound lens consisting of one element (single lens) or more than one element cemented or otherwise joined together. A lens may therefore be described as 4-element, 3-component when two of the elements are cemented together.

Composition

The pleasing arrangement of the elements within a scene-the main subject, the foreground and background, and supporting subjects.

Computerised flash.

Electronic flash guns which sense the light reflected from the subject, and cut off their output when they have received sufficient light for correct exposure. Most units must be used on or close to the camera for direct lighting only. And the camera lens must be set to a specific aperture (or a small range of apertures) determined by the speed of the film in use.

Condenser.

Generally a simple lens used to collect light and concentrate it on a particular area, as in enlarger or projector. Frequently in the form of two planoconvex lenses in a metal housing. A condenser, normally of the fresnel type, is used to ensure even illumination of the viewing screens on SLR cameras.

Condenser Enlarger

An enlarger with a sharp, undiffused light that produces high contrast and high definition in a print. Scratches and blemishes in the negative are emphasised.

Contact Print

A print made by exposing photographic paper while it is held tightly against the negative. Images in the print will be the same size as those in the negative.

Contrast

The range of difference in the light to dark areas of a negative, print, or slide (also called density); the brightness range of a subject or the scene lighting. It may be also explained as tonal difference. More often used to compare original and reproduction. A negative may be said to be contrasty if it shows fewer, more widely spaced tones than in the original.

Or another way to explain, a difference in visual brilliance between one part of the image and another; without contrast, there would be no such thing as a visible image; a line in a photograph is visible only because it is either darker or lighter in tone than the background; every distinguishable part of the image is the result of a contrast in tonal values.

Contact Printer

A device used for contact-printing that consists of a lighttight box with an internal light source and a printing frame to position the negative against the photographic paper in front of the light.

Continuous Servo AF Focus

Autofocus term used by Nikon, the AF sensor detection continues as long as shutter release button is lightly pressed and the reflex mirror is in the viewing position. Useful when the camera-to-subject distance is likely to change.

Contrast Grade

Numbers (usually 1-5) and names (soft, medium, hard, extra-hard, and ultra hard) of the contrast grades of photographic papers, to enable you to get good prints from negatives of different contrasts. Use a low-numbered or soft contrast paper with a high contrast negative to get a print that most closely resembles the original scene. Use a high-numbered or an extra-hard paper with a low-contrast negative to get a normal contrast paper.

Contrasty

Higher-than-normal contrast including very bright and dark areas. The range of density in a negative or print is higher than it was in the original scene.

Coma

A lens aberration restricted to off axis image points; the inability of a lens to render point sources of light near the edges of the frame as circular; the points of light appear as comet-shaped blurs (hence the name coma) with the tails flaring toward the center of the image; this aberration is very difficult to eliminate in wideangle lenses with large maximum apertures; improves by stopping down the lens.

Continuous Servo (Nikon's term) :

AF Focus detection continues as long as shutter release button is lightly pressed and the reflex mirror is in the viewing position. Useful when the camera-to subject distance is likely to change.

CPU (Central Processing Unit)

The electronic component that controls an electronic product's functions. Essentially, all automatic cameras have at least a CPU to control various functions of the cameras. Some top models have three to five CPU to handle individual task functions - some handle the exposure, one handle the autofocus and so on. The latest on some top models utilising 8 or 16 bits chips now. Newer autofocus lenses have built-in CPUs to relay information relating to focal length, distance info, lens type to the camera body for exposure to AF processing.

Cropping

Printing only part of the image that is in the negative or slide, usually for a more pleasing composition, in medium format, esp the 6 x 6, some form of cropping is necessary for publishing on A4 magazine format. May also refer to the framing of the scene in the viewfinder.

Curvature of Field. This optical defect causes points on an object plane perpendicular to the lens axis to focus on a curved surface rather than a plane.

C 41

Kodak's standard chemical process for developing color negative film, an industrial reference standard.