A Glossary of Common Photographic Terms

Extracted from www.kodak.com

Aperture
Lens opening. The opening in a camera lens through which light passes to expose the film. The size of aperture is either fixed or adjustable. Aperture size is usually calibrated in f-numbers-the larger the number, the smaller the lens opening.

Autofocus (AF)
System by which the camera lens automatically focuses the image of a selected part of the picture subject.

Backlighting
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.

Balance
Placement of colors, light and dark masses, or large and small objects in a picture to create harmony and equilibrium.

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 or effect.

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.

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.

Color Noise
Better known as chrominance signal-to-noise ratio. A measure of how accurately the color signals are reproduced. Poor chroma signal-to-noise ratios are evidenced in color fringing on edges of objects and what appears to be thousands of moving dots in large areas of highly saturated colors (especially red).

Cropping
Printing only part of the image that is in the negative or slide, usually for a more pleasing composition. May also refer to the framing of the scene in the viewfinder.

Depth of Field
The amount of distance between the nearest and farthest objects that appear in acceptably sharp focus in a photograph. Depth of field depends on the lens opening, the focal length of the lens, and the distance from the lens to the subject.

Exposure
The quantity of light allowed to act on a photographic material; a product of the intensity (controlled by the lens opening) and the duration (controlled by the shutter speed or enlarging time) of light striking the film or paper.

Film Speed
The sensitivity of a given film to light, indicated by a number such as ISO 200. The higher the number, the more sensitive or faster the film. Note: ISO stands for International Standards Organization.
Filter
A colored piece of glass or other transparent material used over the lens to emphasize, eliminate, or change the color or density of the entire scene or certain areas within a scene.

f-Number
A number that indicates the size of the lens opening on an adjustable camera. The common f-numbers are f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, and f/22. The larger the f-number, the smaller the lens opening. In this series, f/1.4 is the largest lens opening and f/22 is the smallest. Also called f-stops, they work in conjunction with shutter speeds to indicate exposure settings.

Focus
Adjustment of the distance setting on a lens to define the subject sharply.

Hot Shoe
The fitting on a camera that holds a small portable flash. It has an electrical contact that aligns with the contact on the flash unit's "foot" and fires the flash when you press the shutter release. This direct flash-to-camera contact eliminates the need for a PC cord.

ISO Speed
The emulsion speed (sensitivity) of the film as determined by the standards of the International Standards Organization. In these standards, both arithmetic (ASA) and logarithmic (DIN) speed values are expressed in a single ISO term. For example, a film with a speed of ISO 100/21 would have a speed of ASA 100 or 21 DIN.

Lens Speed
The largest lens opening (smallest f-number) at which a lens can be set. A fast lens transmits more light and has a larger opening than a slow lens.

Macro Lens
A lens that provides continuous focusing from infinity to extreme close-ups, often to a reproduction ratio of 1:2 (half life-size) or 1:1 (life-size).

Saturation
An attribute of perceived color, or the percentage of hue in a color. Saturated colors are called vivid, strong, or deep. Desaturated colors are called dull, weak, or washed out.

Selective Focus
Choosing a lens opening that produces a shallow depth of field. Usually this is used to isolate a subject by causing most other elements in the scene to be blurred.

Shutter
Blades, a curtain, plate, or some other movable cover in a camera that controls the time during which light reaches the film.

Shutter Priority
An exposure mode on an automatic or autofocus camera that lets you select the desired shutter speed; the camera sets the aperture for proper exposure. If you change the shutter speed, or the light level changes, the camera adjusts the aperture automatically.

Stopping Down
Changing the lens aperture to a smaller opening; for example, from f/8 to f/11.

Vignetting
A fall-off in brightness at the edges of an image, slide, or print. Can be caused by poor lens design, using a lens hood not matched to the lens, or attaching too many filters to the front of the lens.

Wide-Angle Lens
A lens that has a shorter focal length and a wider field of view (includes more subject area) than a normal lens.

Zoom Lens
A lens in which you adjust the focal length over a wide range. In effect, this gives you lenses of many focal lengths.