How rich the colors are in a photo.

Light intensity that exceeds the maximum level designed for a CCD.

The part of the scanner containing fluorescent lamps that passes across an image.

A device that captures an image for your computer and converts it to a digital form that your computer can display, edit store and output. A scanner can be used for a wide variety of application, such as incorporating artwork or photos into documents, scanning printed text into your word processor to eliminate retyping, scanning faxed document into a database for storage, and adding images to multimedia productions.

Setting that determines whether a pixel is white or black.

The angle at which the halftone screens are placed in relation to one another.

See lpi.

The size of the rectangular grid of pixels displayed on a monitor.

Number of raster points either per inch or per centimetre. Measured in lines per cm (l/cm) or lines per inch (lpi). A 60 l/cm raster therefore corresponds with 152 lpi.

Another name for halftoning.

An acronym for Small Computer System Interface. An industry standard interface that provides high-speed access to peripheral devices.

A group of SCSI devices linked to each other through SCSI peripheral interface cables and linked to the SCSI port on the computer through a SCSI system cable.

A number assigned to each SCSI device connected to a computer. The Macintosh itself is assigned ID 7. Other devices may use IDs 6 through 0, with 6 indicating the highest priority for communications and 0 the lowest priority.

A port that's faster than the serial and parallel ports but slower and harder to configure than the newer USB port. Also know as the Small Computer System Interface.

See ISO speed.

A method for connecting an external device such as a printer, scanner, or camera, to a computer. It has been all but replaced by USB and FireWire in modern computers.

A business that specialises in printing computer files on an imagesetter.

The brightness or luminance of an image when compared to a gray scale.

A term that refers to the amount of detail contained in the dark parts of an image. It is desirable to maintain shadow detail but there is a risk of decreasing overall contrast if one lightens the shadow too much in an attempt to expose detail. If an image is scanned without shadow detail, it will be impossible to regain detail in an image editing program.

The darkest tone printable in an image without being black. All tonal values below this threshold will print as black.

The black and nearly black tones in an image.

Electronic photo-retouching function for enhancing image detail and contrast either globally or in selected regions of the picture.

An image editor technique to enhance the edge of an object.

An image degree of clarity in terms of focus and contrast.

Film that is cut into individual flat piece. Used in large format view camera, with sizes like 4x5, 8x10 and 11x14 inches. Also called cut film.

Is the length of time unused material or chemicals will remain fresh.

"Movement on large format camera (or special "shift lens" in other formats) which can eliminate converging angles."

Refers to the distance between the subject and the film plane.

The amount of control you have in choosing how your digital camera captures an image. All digital cameras usually have an Auto mode: the camera decides for you the best shutter speed/aperture settings.

Term describing a wide-angle lens (a lens whose focal length is shorter than the diagonal measurement of the film used).

The mechanical or electromechanical button that releases the shutter and takes the exposure.

The duration that the shutter is held open during an exposure. A typical range is from 1 full second to 1/1000 of a second. Combined with the lens aperture it controls the total amount of exposure.

The ratio of the usable signal to unusable noise in a scan. A high degree of noise can mask the shadow detail in an image regardless of tonal resolution.

Standing for single-lens reflex, these are higher-end digital cameras revered by serious photographers. The digital versions of SLRs work in this manner: the shutter retracts so an image can be recorded. One of the prime benefits of using a digital SLR camera is that lenses are interchangeable.

A wafer-thin, matchbook size memory card. This is also a flash-memory based storage medium.

Colour information stored as multiple measurements (typically 16 32, or more ) across the range of wavelengths of visible light.

A device that captures colours as spectral data, thereby providing maximum accuracy in measuring and specifying colours.

A bright reflection from a light source containing little or no detail. Specular highlight within an image should not be used for Set Whitepoint.

"Light rays that are highly redirected at or near the same angle of incidence to a surface. Observation at this angle allows the viewer to "see" the light source."

A measure of the sensitivity to light of a photographic emulsion.

Light passing through a convex lens will be brought to different focus depending upon whether the light passes through near the center of the lens or closer to the periphery. Lens designers strive to correct this kind of zonal aberration to bring peripheral and near-central rays to a common focus.

Autoexposure is based on a meter reading of a small circle in the center of the viewfinder.

A calibrated RGB colour space, proposed as a Web standard.

Standard resolution is 640 x 480 pixels (H x V) and originates with the VGA standard first defined for the IBM PC. SVGA is the next step up in terms of resolution and covers 800 x 600. XGA define the 1024 x 768 resolution, while UXGA is used for 1280x1024 and 1600x1200. The higher the resolution the finer the image detail that can be seen.

The traditional process of assembling colour separations and typeset text by hand prior to making printing press plates.

Using an algorithm to derive a lower-resolution image from a higher-resolution image.

"Combining cyan, magenta and yellow inks (or other colourants ) to create black

The ink colours cyan, magenta, and yellow that add together to make black.