Glossary

Threshold

The limit up to which Unsharp Mask will be applied. While it is generally the case that the higher the threshold, the greater the amount of sharpening applied, the exact effect depends on other Unsharp Mask settings, such as halo width. See also Halo width, Unsharp Mask.

Thumbnail

A small preview image, the digital equivalent of a photographic film contact sheet. Images loaded into Nikon Capture are displayed in a thumbnail list in the Thumbnails section of the Camera Image window.

TIFF

Tagged Image File Format, an image file format for color or grayscale images, suited to stor- ing bit-mapped images such as digital photographs. In some implementations, TIFF supports “lossless” LZW and packbit compression (in “lossless” compression methods, no information is lost when the image is compressed, as opposed to “lossy” compression methods such as JPEG, in which detail is sacrificed to achieve higher compression ratios). LZW compression is available when saving TIFF (RGB) images in Nikon Capture 4 Ver. 4.3 or later. See also Com- pression, JPEG.

Tone

Pixel brightness, measured either as the combined intensity for red, green, and blue or the intensity of each of these colors (channels) individually. The number of tones that can be expressed depends on the bit depth of the image; Nikon Capture 4 supports 256 tone levels per channel at a bit depth of eight bits and 4096 tone levels per channel at a bit depth of twelve bits (data with a bit depth of twelve bits are handled internally as sixteen-bit data). The distribution of tones in the image can be seen in the Curves window histogram. See also Bit depth.

Tone curve

A visual tool for editing tones, enhancing brightness and contrast in a selected portion of the tone range. Changing the shape of the tone curve changes the mapping between input (the tones in the original image) and output (tones as they appear after editing). The digital equivalent of a densitometric curve. See also Tone.

Unsharp Mask

A filter for increasing the apparent sharpness of bit-mapped images. Sometimes abbreviated as “USM.” Unsharp masks emphasize the differences in color and brightness between edges (outlines) and the rest of the image. See also Halo width, Threshold.

USB

Universal Serial Bus. A standard for computer serial interfaces which allows automatic “plug- and-play” recognition of peripheral devices and “hot plug” connection of peripherals while the computer or device is on. Depending on the type of interface installed on the computer, USB will operate at high speed (USB 2.0 only), with data transfer rates of up to 480 Mbps, or full speed (USB 1.1, USB 2.0), with data transfer rates of up to 12 Mbps. For more information, consult the manufacturer.

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