U
  • UCR
    (Undercolour Removal) A technique for reducing the amount of magenta, Yellow, and cyan ink in neutral areas of an image and replacing them with an appropriate amount of black ink.

  • Undercolour removal (UCR)
    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.

  • Underexposure
    Exposing the film to less light than is needed to render the scene as the eye sees it. Results in a too dark photograph.

  • Unsharp masking
    "A process by which the apparent detail of an image is increased

  • Untagged
    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.

  • USB
    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.