ULTRASONIC IMAGE RECORDING

Definition: image formation by measurement of ultrasound echoes translated electronically into a scanned visual image on a TV display. Also known as sonography.

ULTRAVIOLET

Definition: The part of the spectrum just beyond violet. Ultraviolet light is invisible to the human eye but strongly affects photographic materials.

ULTRAVIOLET (UV)

Definition: part of the electromagnetic spectrum from about 400nm down to 1nm. It is invisible to the human eye, but most photographic materials are sensitive to near UV bands down to 250nm. It records as increased haze, particularly in distant views and at high altitudes, and may give a blue cast in color images. technique of projecting an infrared image on a phosphorescent surface.

UNDER-DEVELOPMENT

Definition: Is a reduction in the degree of development. It is usually caused by shortened development time or a decrease in the temperature of the solution. It results in a loss of density and a reduction in image contrast.

UNDERCOLOUR REMOVAL

Definition: A separation technique in which black ink is used to replace approximately equal amounts of cyan, magenta, and yellow ink in neutral tones, primarily in the shadows, so as to reduce the total ink coverage.

UNDERDEVELOP

Definition: To give less development than normal.

UNDEREXPOSE

Definition: To give less than normal exposure to film or paper. The resulting silver density is often less than necessary for best results.

UNDEREXPOSURE

Definition: A condition in which too little light reaches the film, producing a thin negative, a dark slide, or a muddy-looking print.

Definition: result of too little exposure in the camera or at the enlargement stage.

UNIPOD

Definition: A one-legged support used to hold the camera steady.

Definition: A " Monopod," a single-legged camera support that functions in a manner similar to a tripod.

UNIVERSAL DEVELOPER

Definition: name given to a number of developing solutions, usually MQ, indicating that they can be used for processing films and papers.

UNSHARP MASKING

Definition: A process by which the apparent detail of an image is increased; generally accomplished by the input scanner or through computer manipulation.

UNSHARP MASKING (USM)

Definition: The sharpening of an image by creating contrast at contrasting edges of the element.

UNTAGGED

Definition: A Photoshop file that does not contain an embedded ICC profile. To be used in a colour-managed workflow an untagged image must be resaved in Photoshop (with the Embed profile checkbox selected) or tagged with the assign profile command.

UNZIP

Definition: To decompress a file (usually text) using PKUNZIP or WinZip, two popular programs. The decompression takes place automatically when a Zip compressed file is opened (See Zip).

UPGRADE

Definition: To improve some aspect of a computer system. Upgrades include the newest versions of software applications, computer models or peripheral devices. Usually, upgrades are denoted by a version number.

UPRATING

Definition: no longer used term to define the process of increasing the manufacturers film speed by the use of: hypersensitizing; using specially prepared proprietary developers; or by a two stage process.

URANIUM NITRATE

Definition: chemical used in toners and developers.

URL

Definition: Uniform Resource Locator. A standard addressing scheme used to locate or references file on the Internet. Used in World Wide Web documents to locate other files. A URL gives the type of resources (scheme) being accessed and the path to the file. The syntax used is: Scheme://host. domain;port/path filename.

USB

Definition: Universal serial bus. The USB offers a simplified way to attach peripherals and have them recognized by the computer. USB ports are about 10 times faster than a typical serial connection. These USB ports are usually located in easy to access locations on the computer.

Definition: Universal Serial Bus: a protocol for transferring data to and from digital devices. Many digital cameras and memory card readers connect to the USB port on a computer. USB card readers are typically faster than cameras or readers that connect to the serial port, but slower than those that connect via FireWire.

USM

Definition: ( Unsharp Mask ) The term comes from a conventional colour separation camera technique that uses a unsharp photographic mask to increase contrast between light and dark areas of the reproduction and gives the illusion of sharpness.