Operation Manual

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Appendices
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Appendices— Appendix B
JPEG
A standard graphic format designed by the Joint Photographic Experts Group. Images are compressed using a discrete cosine
transform that takes advantage of the properties of hu man vision, which is more sensitive to light in the lower wavelengths,
to increase quantization at lower frequencies. JPEG com pres sion is “lossy,” meaning that information is lost when images are
compressed, leading to a drop in image quality. A lossless compression option is also supported in some implementations.
JPEG images can be compressed to as much as 100:1, though quality will be signifi cantly reduced. At a compression ratio of
20 : 1, image quality is not noticeably diminished.
Term Defi nition
NEF
Nikon Electronic Image Format, an image fi le format developed by Nikon to support high-resolution image data. In Windows,
NEF fi les have the ex ten sion “.nef”. The advantage of NEF is that while user settings such as curves and color balance are saved,
they are not applied to the original image data. NEF images may thus be edited and saved several times without degrading or
altering the original image.
Noise
Digital “artifacts,” or data in an image fi le that are not a part of the original image. The presence of noise is refl ected in a loss
in image quality.
ppcm
pixels per centimeter, a measure of resolution. The more pixels per centimeter, the higher the res o lu tion. See also ppi, Reso-
lution.
ppi pixels per inch, a measure of resolution. The more pixels per inch, the higher the resolution. See also ppcm, Resolution.
Preferences Settings controlling basic operations performed by a given program, adjustable by the user.
Profi le
A fi le defi ning the color characteristics of an input device such as a scanner or digital camera, an output device such as a printer
or monitor, or the color space used for editing images. Profi les are used by color management systems to ensure consistent col-
or reproduction. The Nikon Color Management System used in Nikon Scan employs ICC profi les. See also Color space, ICC.
Resolution
The density of dots or pixels that make up an image, measured in dots per inch (dpi) or pixels per inch (ppi); the resolution of
Windows monitors, for example, is 96 ppi. The greater the density of dots or pixels, the higher the resolution and the greater
the capacity to express detail. Resolution is hence the digital equivalent of fi lm resolving power. Computer monitors typically
have a resolution of 72 ppi, 90 ppi, or 96 ppi, while printers may have resolutions of 300 dpi, 600 dpi, 1200 dpi, or 2400 dpi. See
also ppcm, ppi.
Plug-in A software module that adds functionality to another application.
IEEE 1394
A high-speed transfer protocol developed by the Institute of Electrical and Electronics En gi neers for connecting peripherals such
as hard disks, MO drives, and digital cameras to a com put er via a cable.